单项选择题

Questions 11 to 13 are based on the following passage. At the end of the passage, you will be given 15 seconds to answer the questions. Now listen to the passage. Based on the passage, how many of one hundred and twenty American couples of the beat generation practiced cohabitation

A.About 20 couples.
B.About 30 couples.
C.About 60 couples.
D.About 40 couples.