B. Read the passage carefully, then choose the correct answer.

Normally a student must attend a certain number of courses in order to graduate, and each course which he attends gives him a credit which he may count towards a degree. In many American universities the total work for a degree consists of thirty-six courses each lasting for one semester.

A typical course consists of three classes per week for fifteen weeks; while attending university a student will probably attend two terms each year. It is possible to spread the period of work for the degree over a longer period. It is also possible for a student to move between one university and another during his degree course, though this is not in fact done as a regular practice.

For every course that he follows a student is given a grade, which is recorded, and the record is useful for the student to show to coming employers. Most of the students feel the pressure of work, but in spite of this some students still find time for great activity in student affairs. The students are interested in elections to positions in student organization. The effective work of keeping orders is usually performed by students who advise the university authorities. Any student who is thought to have broken the rules, for example, by cheating has to appear before a student court. With the large numbers of students, the operation of the system includes a certain amount of activity. A student who has held one of these positions is much respected and it will be of importance to him later in his career.

According to the first paragraph an American is allowed _____________ .