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* Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.     In addition to improved physical health, sport plays a primarily positive role in youth development, including improved academic achievement, higher self- esteem, fewer behavioural problems, and better psychosocial development. Many studies focus on the effects of sport on the five “C’ s” - competence, confidence, connections, character, and caring The many facets of playing sport - the discipline of training, learning teamwork, following the leadership of coaches and captains, learning to lose - provide lifelong skills for athletes.      The literature on youth sport stresses the positive effects of participation in learning the important life skills of goal setting and time management combined with enjoyment; the development of a strong sense of morality; and the development of an appreciation of diversity. Studies have shown that children and youth participating in sport, when compared to peers who do not play sport, exhibit higher grades, expectations, and attainment; greater personal confidence and self-esteem; greater connections with school — that is, greater attachment and support from adults; stronger peer relationships; more academically oriented friends; greater family attachment and more frequent interactions with parents; more restraint in avoiding risky behaviour; and greater involvement in volunteer work.      Sport provides opportunities for children and youth to engage in valuable and positive relationships with adults. Thus, it is a missed opportunity for children who are “gated” - or not included in sport - during early stages of childhood because they are less well behaved than other children. These children are being prevented from participating in the very thing that could help them learn to control and regulate their behaviour. Sport provides an opportunity for children to safely navigate and negotiate between right and wrong as they learn to interact with peers and adults. Research by Taliaferro et al. suggests that playing sport can even protect against suicide risk in youth. Compared to nonathletes, male athletes exhibit lower levels of hopelessness and suicidal ideation. Young males involved in multiple sports seem to gamer even more protection in this regard. Similar results were found for girls. Research on the role of exercise in adults confirms that it improves mood and alleviates many forms of depression. Bartko and Eccles found that youth who are highly involved in sport are more “psychologically resilient,” that is, better able to recover from problems. Eccles et al. found that sport participation protects young athletes against social isolation.(Adaptedfrom: Sport is a way of life, Sun Star Baguio, Jan 10, 2017)What is the best title for the passage?
* Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.     In addition to improved physical health, sport plays a primarily positive role in youth development, including improved academic achievement, higher self- esteem, fewer behavioural problems, and better psychosocial development. Many studies focus on the effects of sport on the five “C’ s” - competence, confidence, connections, character, and caring The many facets of playing sport - the discipline of training, learning teamwork, following the leadership of coaches and captains, learning to lose - provide lifelong skills for athletes.      The literature on youth sport stresses the positive effects of participation in learning the important life skills of goal setting and time management combined with enjoyment; the development of a strong sense of morality; and the development of an appreciation of diversity. Studies have shown that children and youth participating in sport, when compared to peers who do not play sport, exhibit higher grades, expectations, and attainment; greater personal confidence and self-esteem; greater connections with school — that is, greater attachment and support from adults; stronger peer relationships; more academically oriented friends; greater family attachment and more frequent interactions with parents; more restraint in avoiding risky behaviour; and greater involvement in volunteer work.      Sport provides opportunities for children and youth to engage in valuable and positive relationships with adults. Thus, it is a missed opportunity for children who are “gated” - or not included in sport - during early stages of childhood because they are less well behaved than other children. These children are being prevented from participating in the very thing that could help them learn to control and regulate their behaviour. Sport provides an opportunity for children to safely navigate and negotiate between right and wrong as they learn to interact with peers and adults. Research by Taliaferro et al. suggests that playing sport can even protect against suicide risk in youth. Compared to nonathletes, male athletes exhibit lower levels of hopelessness and suicidal ideation. Young males involved in multiple sports seem to gamer even more protection in this regard. Similar results were found for girls. Research on the role of exercise in adults confirms that it improves mood and alleviates many forms of depression. Bartko and Eccles found that youth who are highly involved in sport are more “psychologically resilient,” that is, better able to recover from problems. Eccles et al. found that sport participation protects young athletes against social isolation.(Adaptedfrom: Sport is a way of life, Sun Star Baguio, Jan 10, 2017)Whose study suggests that sport players are more able to feel better after unpleasant events than others?
* Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.     In addition to improved physical health, sport plays a primarily positive role in youth development, including improved academic achievement, higher self- esteem, fewer behavioural problems, and better psychosocial development. Many studies focus on the effects of sport on the five “C’ s” - competence, confidence, connections, character, and caring The many facets of playing sport - the discipline of training, learning teamwork, following the leadership of coaches and captains, learning to lose - provide lifelong skills for athletes.      The literature on youth sport stresses the positive effects of participation in learning the important life skills of goal setting and time management combined with enjoyment; the development of a strong sense of morality; and the development of an appreciation of diversity. Studies have shown that children and youth participating in sport, when compared to peers who do not play sport, exhibit higher grades, expectations, and attainment; greater personal confidence and self-esteem; greater connections with school — that is, greater attachment and support from adults; stronger peer relationships; more academically oriented friends; greater family attachment and more frequent interactions with parents; more restraint in avoiding risky behaviour; and greater involvement in volunteer work.      Sport provides opportunities for children and youth to engage in valuable and positive relationships with adults. Thus, it is a missed opportunity for children who are “gated” - or not included in sport - during early stages of childhood because they are less well behaved than other children. These children are being prevented from participating in the very thing that could help them learn to control and regulate their behaviour. Sport provides an opportunity for children to safely navigate and negotiate between right and wrong as they learn to interact with peers and adults. Research by Taliaferro et al. suggests that playing sport can even protect against suicide risk in youth. Compared to nonathletes, male athletes exhibit lower levels of hopelessness and suicidal ideation. Young males involved in multiple sports seem to gamer even more protection in this regard. Similar results were found for girls. Research on the role of exercise in adults confirms that it improves mood and alleviates many forms of depression. Bartko and Eccles found that youth who are highly involved in sport are more “psychologically resilient,” that is, better able to recover from problems. Eccles et al. found that sport participation protects young athletes against social isolation.(Adaptedfrom: Sport is a way of life, Sun Star Baguio, Jan 10, 2017)Which of the followings is NOT prevented as a result of playing sports?
* Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.     In addition to improved physical health, sport plays a primarily positive role in youth development, including improved academic achievement, higher self- esteem, fewer behavioural problems, and better psychosocial development. Many studies focus on the effects of sport on the five “C’ s” - competence, confidence, connections, character, and caring The many facets of playing sport - the discipline of training, learning teamwork, following the leadership of coaches and captains, learning to lose - provide lifelong skills for athletes.      The literature on youth sport stresses the positive effects of participation in learning the important life skills of goal setting and time management combined with enjoyment; the development of a strong sense of morality; and the development of an appreciation of diversity. Studies have shown that children and youth participating in sport, when compared to peers who do not play sport, exhibit higher grades, expectations, and attainment; greater personal confidence and self-esteem; greater connections with school — that is, greater attachment and support from adults; stronger peer relationships; more academically oriented friends; greater family attachment and more frequent interactions with parents; more restraint in avoiding risky behaviour; and greater involvement in volunteer work.      Sport provides opportunities for children and youth to engage in valuable and positive relationships with adults. Thus, it is a missed opportunity for children who are “gated” - or not included in sport - during early stages of childhood because they are less well behaved than other children. These children are being prevented from participating in the very thing that could help them learn to control and regulate their behaviour. Sport provides an opportunity for children to safely navigate and negotiate between right and wrong as they learn to interact with peers and adults. Research by Taliaferro et al. suggests that playing sport can even protect against suicide risk in youth. Compared to nonathletes, male athletes exhibit lower levels of hopelessness and suicidal ideation. Young males involved in multiple sports seem to gamer even more protection in this regard. Similar results were found for girls. Research on the role of exercise in adults confirms that it improves mood and alleviates many forms of depression. Bartko and Eccles found that youth who are highly involved in sport are more “psychologically resilient,” that is, better able to recover from problems. Eccles et al. found that sport participation protects young athletes against social isolation.(Adaptedfrom: Sport is a way of life, Sun Star Baguio, Jan 10, 2017)What does the word “gated” in the third paragraph mean?
* Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.     In addition to improved physical health, sport plays a primarily positive role in youth development, including improved academic achievement, higher self- esteem, fewer behavioural problems, and better psychosocial development. Many studies focus on the effects of sport on the five “C’ s” - competence, confidence, connections, character, and caring The many facets of playing sport - the discipline of training, learning teamwork, following the leadership of coaches and captains, learning to lose - provide lifelong skills for athletes.      The literature on youth sport stresses the positive effects of participation in learning the important life skills of goal setting and time management combined with enjoyment; the development of a strong sense of morality; and the development of an appreciation of diversity. Studies have shown that children and youth participating in sport, when compared to peers who do not play sport, exhibit higher grades, expectations, and attainment; greater personal confidence and self-esteem; greater connections with school — that is, greater attachment and support from adults; stronger peer relationships; more academically oriented friends; greater family attachment and more frequent interactions with parents; more restraint in avoiding risky behaviour; and greater involvement in volunteer work.      Sport provides opportunities for children and youth to engage in valuable and positive relationships with adults. Thus, it is a missed opportunity for children who are “gated” - or not included in sport - during early stages of childhood because they are less well behaved than other children. These children are being prevented from participating in the very thing that could help them learn to control and regulate their behaviour. Sport provides an opportunity for children to safely navigate and negotiate between right and wrong as they learn to interact with peers and adults. Research by Taliaferro et al. suggests that playing sport can even protect against suicide risk in youth. Compared to nonathletes, male athletes exhibit lower levels of hopelessness and suicidal ideation. Young males involved in multiple sports seem to gamer even more protection in this regard. Similar results were found for girls. Research on the role of exercise in adults confirms that it improves mood and alleviates many forms of depression. Bartko and Eccles found that youth who are highly involved in sport are more “psychologically resilient,” that is, better able to recover from problems. Eccles et al. found that sport participation protects young athletes against social isolation.(Adaptedfrom: Sport is a way of life, Sun Star Baguio, Jan 10, 2017)Which of the followings is NOT mentioned as a benefit for teenagers playing sport in comparison with those who do not?
* Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.     In addition to improved physical health, sport plays a primarily positive role in youth development, including improved academic achievement, higher self- esteem, fewer behavioural problems, and better psychosocial development. Many studies focus on the effects of sport on the five “C’ s” - competence, confidence, connections, character, and caring The many facets of playing sport - the discipline of training, learning teamwork, following the leadership of coaches and captains, learning to lose - provide lifelong skills for athletes.      The literature on youth sport stresses the positive effects of participation in learning the important life skills of goal setting and time management combined with enjoyment; the development of a strong sense of morality; and the development of an appreciation of diversity. Studies have shown that children and youth participating in sport, when compared to peers who do not play sport, exhibit higher grades, expectations, and attainment; greater personal confidence and self-esteem; greater connections with school — that is, greater attachment and support from adults; stronger peer relationships; more academically oriented friends; greater family attachment and more frequent interactions with parents; more restraint in avoiding risky behaviour; and greater involvement in volunteer work.      Sport provides opportunities for children and youth to engage in valuable and positive relationships with adults. Thus, it is a missed opportunity for children who are “gated” - or not included in sport - during early stages of childhood because they are less well behaved than other children. These children are being prevented from participating in the very thing that could help them learn to control and regulate their behaviour. Sport provides an opportunity for children to safely navigate and negotiate between right and wrong as they learn to interact with peers and adults. Research by Taliaferro et al. suggests that playing sport can even protect against suicide risk in youth. Compared to nonathletes, male athletes exhibit lower levels of hopelessness and suicidal ideation. Young males involved in multiple sports seem to gamer even more protection in this regard. Similar results were found for girls. Research on the role of exercise in adults confirms that it improves mood and alleviates many forms of depression. Bartko and Eccles found that youth who are highly involved in sport are more “psychologically resilient,” that is, better able to recover from problems. Eccles et al. found that sport participation protects young athletes against social isolation.(Adaptedfrom: Sport is a way of life, Sun Star Baguio, Jan 10, 2017) According to the passage, sport players benefit from___________.
* Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.     In addition to improved physical health, sport plays a primarily positive role in youth development, including improved academic achievement, higher self- esteem, fewer behavioural problems, and better psychosocial development. Many studies focus on the effects of sport on the five “C’ s” - competence, confidence, connections, character, and caring The many facets of playing sport - the discipline of training, learning teamwork, following the leadership of coaches and captains, learning to lose - provide lifelong skills for athletes.      The literature on youth sport stresses the positive effects of participation in learning the important life skills of goal setting and time management combined with enjoyment; the development of a strong sense of morality; and the development of an appreciation of diversity. Studies have shown that children and youth participating in sport, when compared to peers who do not play sport, exhibit higher grades, expectations, and attainment; greater personal confidence and self-esteem; greater connections with school — that is, greater attachment and support from adults; stronger peer relationships; more academically oriented friends; greater family attachment and more frequent interactions with parents; more restraint in avoiding risky behaviour; and greater involvement in volunteer work.      Sport provides opportunities for children and youth to engage in valuable and positive relationships with adults. Thus, it is a missed opportunity for children who are “gated” - or not included in sport - during early stages of childhood because they are less well behaved than other children. These children are being prevented from participating in the very thing that could help them learn to control and regulate their behaviour. Sport provides an opportunity for children to safely navigate and negotiate between right and wrong as they learn to interact with peers and adults. Research by Taliaferro et al. suggests that playing sport can even protect against suicide risk in youth. Compared to nonathletes, male athletes exhibit lower levels of hopelessness and suicidal ideation. Young males involved in multiple sports seem to gamer even more protection in this regard. Similar results were found for girls. Research on the role of exercise in adults confirms that it improves mood and alleviates many forms of depression. Bartko and Eccles found that youth who are highly involved in sport are more “psychologically resilient,” that is, better able to recover from problems. Eccles et al. found that sport participation protects young athletes against social isolation.(Adaptedfrom: Sport is a way of life, Sun Star Baguio, Jan 10, 2017)According to the passage what is NOT increased by playing sports?
* Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.     In addition to improved physical health, sport plays a primarily positive role in youth development, including improved academic achievement, higher self- esteem, fewer behavioural problems, and better psychosocial development. Many studies focus on the effects of sport on the five “C’ s” - competence, confidence, connections, character, and caring The many facets of playing sport - the discipline of training, learning teamwork, following the leadership of coaches and captains, learning to lose - provide lifelong skills for athletes.      The literature on youth sport stresses the positive effects of participation in learning the important life skills of goal setting and time management combined with enjoyment; the development of a strong sense of morality; and the development of an appreciation of diversity. Studies have shown that children and youth participating in sport, when compared to peers who do not play sport, exhibit higher grades, expectations, and attainment; greater personal confidence and self-esteem; greater connections with school — that is, greater attachment and support from adults; stronger peer relationships; more academically oriented friends; greater family attachment and more frequent interactions with parents; more restraint in avoiding risky behaviour; and greater involvement in volunteer work.      Sport provides opportunities for children and youth to engage in valuable and positive relationships with adults. Thus, it is a missed opportunity for children who are “gated” - or not included in sport - during early stages of childhood because they are less well behaved than other children. These children are being prevented from participating in the very thing that could help them learn to control and regulate their behaviour. Sport provides an opportunity for children to safely navigate and negotiate between right and wrong as they learn to interact with peers and adults. Research by Taliaferro et al. suggests that playing sport can even protect against suicide risk in youth. Compared to nonathletes, male athletes exhibit lower levels of hopelessness and suicidal ideation. Young males involved in multiple sports seem to gamer even more protection in this regard. Similar results were found for girls. Research on the role of exercise in adults confirms that it improves mood and alleviates many forms of depression. Bartko and Eccles found that youth who are highly involved in sport are more “psychologically resilient,” that is, better able to recover from problems. Eccles et al. found that sport participation protects young athletes against social isolation.(Adaptedfrom: Sport is a way of life, Sun Star Baguio, Jan 10, 2017)What is NOT mentioned as a factor contributing to lifelong skills for athletes?
* Read the following passage and mark the letter A, R, C, or D on your answer sheet to indicate the correct answer to each of the questions from 24 to 30.People have been donating blood since the early twentieth century to help accident victims and patients undergoing surgical procedures. Usually a pint of whole blood is donated, and it is then divided into platelets, white blood cells, and red blood cells. People can donate blood (for red blood cells) about once every two months.Transfusing the blood from the donor to the recipient is straightforward. It involves taking the blood from a donor’s arm vein by means of a hypodermic syringe. The blood flows down from the container by gravity. This is a slow process and may last as long as 2 hours to complete the infusion of blood into the recipient. The patient is protected from being infected during the transfusion. Only sterile containers, tubing, and needles are used, and this helps ensure that transfused or stored blood is not exposed to disease causing bacteria.Negative reactions to transfusions are not unusual. The recipient may suffer an allergic reaction or be sensitive to donor leukocytes. Some may suffer from an undetected red cell incompatibility. Unexplained reactions are also fairly common. Although they are rare, other causes of such negative reactions include contaminated blood, air bubbles in the blood, overloading of the circulatory system through administration of excess blood, or sensitivity to donor plasma or platelets.Today, hospitals and blood banks go to great lengths to screen all blood donors and their blood. All donated blood is routinely and rigorously tested for diseases, such as HIV, hepatitis B, and syphilis. When the recipient is a newborn or an infant, the blood is usually irradiated to eliminate harmful elements. Donated blood is washed, and the white blood cells and platelets removed.Storing the blood sometimes requires a freezing process. To freeze the red blood cells, a glycerol solution is added. To unfreeze the, the glycerolis removed. The ability to store blood for long periods has been a boon to human health.What does the author imply in the passage?
* Read the following passage and mark the letter A, R, C, or D on your answer sheet to indicate the correct answer to each of the questions from 24 to 30.People have been donating blood since the early twentieth century to help accident victims and patients undergoing surgical procedures. Usually a pint of whole blood is donated, and it is then divided into platelets, white blood cells, and red blood cells. People can donate blood (for red blood cells) about once every two months.Transfusing the blood from the donor to the recipient is straightforward. It involves taking the blood from a donor’s arm vein by means of a hypodermic syringe. The blood flows down from the container by gravity. This is a slow process and may last as long as 2 hours to complete the infusion of blood into the recipient. The patient is protected from being infected during the transfusion. Only sterile containers, tubing, and needles are used, and this helps ensure that transfused or stored blood is not exposed to disease causing bacteria.Negative reactions to transfusions are not unusual. The recipient may suffer an allergic reaction or be sensitive to donor leukocytes. Some may suffer from an undetected red cell incompatibility. Unexplained reactions are also fairly common. Although they are rare, other causes of such negative reactions include contaminated blood, air bubbles in the blood, overloading of the circulatory system through administration of excess blood, or sensitivity to donor plasma or platelets.Today, hospitals and blood banks go to great lengths to screen all blood donors and their blood. All donated blood is routinely and rigorously tested for diseases, such as HIV, hepatitis B, and syphilis. When the recipient is a newborn or an infant, the blood is usually irradiated to eliminate harmful elements. Donated blood is washed, and the white blood cells and platelets removed.Storing the blood sometimes requires a freezing process. To freeze the red blood cells, a glycerol solution is added. To unfreeze the, the glycerolis removed. The ability to store blood for long periods has been a boon to human health.Based on the information in the passage, what can be inferred about blood transfused to infants and newborns?
* Read the following passage and mark the letter A, R, C, or D on your answer sheet to indicate the correct answer to each of the questions from 24 to 30.People have been donating blood since the early twentieth century to help accident victims and patients undergoing surgical procedures. Usually a pint of whole blood is donated, and it is then divided into platelets, white blood cells, and red blood cells. People can donate blood (for red blood cells) about once every two months.Transfusing the blood from the donor to the recipient is straightforward. It involves taking the blood from a donor’s arm vein by means of a hypodermic syringe. The blood flows down from the container by gravity. This is a slow process and may last as long as 2 hours to complete the infusion of blood into the recipient. The patient is protected from being infected during the transfusion. Only sterile containers, tubing, and needles are used, and this helps ensure that transfused or stored blood is not exposed to disease causing bacteria.Negative reactions to transfusions are not unusual. The recipient may suffer an allergic reaction or be sensitive to donor leukocytes. Some may suffer from an undetected red cell incompatibility. Unexplained reactions are also fairly common. Although they are rare, other causes of such negative reactions include contaminated blood, air bubbles in the blood, overloading of the circulatory system through administration of excess blood, or sensitivity to donor plasma or platelets.Today, hospitals and blood banks go to great lengths to screen all blood donors and their blood. All donated blood is routinely and rigorously tested for diseases, such as HIV, hepatitis B, and syphilis. When the recipient is a newborn or an infant, the blood is usually irradiated to eliminate harmful elements. Donated blood is washed, and the white blood cells and platelets removed.Storing the blood sometimes requires a freezing process. To freeze the red blood cells, a glycerol solution is added. To unfreeze the, the glycerolis removed. The ability to store blood for long periods has been a boon to human health.What can the phrase "go to great length" best replaced by?
* Read the following passage and mark the letter A, R, C, or D on your answer sheet to indicate the correct answer to each of the questions from 24 to 30.People have been donating blood since the early twentieth century to help accident victims and patients undergoing surgical procedures. Usually a pint of whole blood is donated, and it is then divided into platelets, white blood cells, and red blood cells. People can donate blood (for red blood cells) about once every two months.Transfusing the blood from the donor to the recipient is straightforward. It involves taking the blood from a donor’s arm vein by means of a hypodermic syringe. The blood flows down from the container by gravity. This is a slow process and may last as long as 2 hours to complete the infusion of blood into the recipient. The patient is protected from being infected during the transfusion. Only sterile containers, tubing, and needles are used, and this helps ensure that transfused or stored blood is not exposed to disease causing bacteria.Negative reactions to transfusions are not unusual. The recipient may suffer an allergic reaction or be sensitive to donor leukocytes. Some may suffer from an undetected red cell incompatibility. Unexplained reactions are also fairly common. Although they are rare, other causes of such negative reactions include contaminated blood, air bubbles in the blood, overloading of the circulatory system through administration of excess blood, or sensitivity to donor plasma or platelets.Today, hospitals and blood banks go to great lengths to screen all blood donors and their blood. All donated blood is routinely and rigorously tested for diseases, such as HIV, hepatitis B, and syphilis. When the recipient is a newborn or an infant, the blood is usually irradiated to eliminate harmful elements. Donated blood is washed, and the white blood cells and platelets removed.Storing the blood sometimes requires a freezing process. To freeze the red blood cells, a glycerol solution is added. To unfreeze the, the glycerolis removed. The ability to store blood for long periods has been a boon to human health.What answer choice is closest in meaning to the word “undetected”?
 * Read the following passage and mark the letter A, R, C, or D on your answer sheet to indicate the correct answer to each of the questions from 24 to 30.People have been donating blood since the early twentieth century to help accident victims and patients undergoing surgical procedures. Usually a pint of whole blood is donated, and it is then divided into platelets, white blood cells, and red blood cells. People can donate blood (for red blood cells) about once every two months.Transfusing the blood from the donor to the recipient is straightforward. It involves taking the blood from a donor’s arm vein by means of a hypodermic syringe. The blood flows down from the container by gravity. This is a slow process and may last as long as 2 hours to complete the infusion of blood into the recipient. The patient is protected from being infected during the transfusion. Only sterile containers, tubing, and needles are used, and this helps ensure that transfused or stored blood is not exposed to disease causing bacteria.Negative reactions to transfusions are not unusual. The recipient may suffer an allergic reaction or be sensitive to donor leukocytes. Some may suffer from an undetected red cell incompatibility. Unexplained reactions are also fairly common. Although they are rare, other causes of such negative reactions include contaminated blood, air bubbles in the blood, overloading of the circulatory system through administration of excess blood, or sensitivity to donor plasma or platelets.Today, hospitals and blood banks go to great lengths to screen all blood donors and their blood. All donated blood is routinely and rigorously tested for diseases, such as HIV, hepatitis B, and syphilis. When the recipient is a newborn or an infant, the blood is usually irradiated to eliminate harmful elements. Donated blood is washed, and the white blood cells and platelets removed.Storing the blood sometimes requires a freezing process. To freeze the red blood cells, a glycerol solution is added. To unfreeze the, the glycerolis removed. The ability to store blood for long periods has been a boon to human health.According to the passage, how often can people donate blood for red blood cells?  
* Read the following passage and mark the letter A, R, C, or D on your answer sheet to indicate the correct answer to each of the questions from 24 to 30.People have been donating blood since the early twentieth century to help accident victims and patients undergoing surgical procedures. Usually a pint of whole blood is donated, and it is then divided into platelets, white blood cells, and red blood cells. People can donate blood (for red blood cells) about once every two months.Transfusing the blood from the donor to the recipient is straightforward. It involves taking the blood from a donor’s arm vein by means of a hypodermic syringe. The blood flows down from the container by gravity. This is a slow process and may last as long as 2 hours to complete the infusion of blood into the recipient. The patient is protected from being infected during the transfusion. Only sterile containers, tubing, and needles are used, and this helps ensure that transfused or stored blood is not exposed to disease causing bacteria.Negative reactions to transfusions are not unusual. The recipient may suffer an allergic reaction or be sensitive to donor leukocytes. Some may suffer from an undetected red cell incompatibility. Unexplained reactions are also fairly common. Although they are rare, other causes of such negative reactions include contaminated blood, air bubbles in the blood, overloading of the circulatory system through administration of excess blood, or sensitivity to donor plasma or platelets.Today, hospitals and blood banks go to great lengths to screen all blood donors and their blood. All donated blood is routinely and rigorously tested for diseases, such as HIV, hepatitis B, and syphilis. When the recipient is a newborn or an infant, the blood is usually irradiated to eliminate harmful elements. Donated blood is washed, and the white blood cells and platelets removed. Storing the blood sometimes requires a freezing process. To freeze the red blood cells, a glycerol solution is added. To unfreeze the, the glycerolis removed. The ability to store blood for long periods has been a boon to human health.The word "it" refers to___________.