[单项选择]

Questions 21-25 are based on the following passage

:
Obviously television has both advantages and disadvantages.
In the first place, television is not only a convenient source of entertainment, but also a cheap one. With a TV set in the family people don’t have to pay for expensive seats at the theatre, or the cinema. Some people, however, think that this is where the danger comes from, The television viewers need do nothing. He makes no choice and exercises, no judgment. He is completely passive.
Television keeps one informed about what is happening. The most distant countries and the strangest customs are brought right into one’s sitting room. On television everything is much more living, much more real. Yet here again there is a danger. We get so used to looking at the movements on it, so dependent on its pictures that it begins to control our lives. People often say that their television sets have broken down and that they have suddenly found that they have far
A. it keeps us informed
B. it is very cheap
C. it enables us to have a rest
D. it controls our lives