Questions 18 to 20 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. The speaker believes the real cause for the increase of divorces today is that ______.
A．people have too many sources of entertainment B．people have less internal restraints C．people no longer enjoy family life as they did before D．people do not want to be confined by marital ties