Choose the letter A, B, C or D to complete the passage below
E-mail, and chat rooms let children (16)______ with friends and family members. They can also allow children (17)_________ with people that they have never met in person. Knowing a little about each of these communication services can help parents (18)________ children safer while online.
Through e-mail, (19)_________can easily send and receive messages. These messages may also have text, audio, and picture files attached. Signing up for an e-mail account is simple because most services offer them (20)_______ free. Sometimes these messages contain viruses, or other inappropriate content, so parents should warn children to be wary of e-mails from unknown people.