听力原文： Cars are an important part of life in the United States. Without a car most of people feel that they are poor. And even if a person is poor he doesn't feel really poor when he has a car.
Henry Ford was the man who first started making cars in large numbers. He probably didn't know how much the car was going to affect American culture. The ear made the United States a nation on wheels. And it helped make the United States what it is today.
There are three main reasons why the car became so popular in the United States. First of all the country is a huge one and Americans like to move around in it. The car provides the most comfortable and cheapest form. of the transportation.
The second reason is the fact that the United States never really developed an efficient and inexpensive form. of public transportation. Long-distance trains have never been as common in the United States as they are in other parts of the world.
The third reason is the most important one, though. The American spirit of independence is what really made cars popular. Americans don't like to wait for a bus, or a train or even a plane. They don't like to follow an exact schedule. A car gives them the freedom to schedule their own time. And this is the freedom that Americans want most to have.
(30)

A. When they don't have a job.
B. When they don't have a car.
C. When they can't afford a house.
D. When they live in a large city.