Reading 2. Choose the correct answer to each of the following questions. Mexico City is growing quickly. In 1970, the city had about 9 million people. Now it has over 17 million. There are not enough jobs and houses. Large families have to live together in small homes. Many homes do not have water and electricity. The Mexican government is working hard to make life better in the city. All around the world, large cities have the same problems. One of them is air pollution. Mexico City is dirty and unhealthy. Cars are one reason for the dirty air. Many Mexicans now have their own cars and drive in the city. The factories in the area also cause air pollution. These factories put a lot of smoke into the air. It is not easy to clean up the air in a large city. The government has to make new laws, and everyone has to help. 1. Large families have to live together in _____________. A. big houses B. modern houses C. comfortable houses D. small houses 2. Why are cars a reason for air pollution? A. Mexico City has pad air. B. Factories put a lot of smoke into the air. C. Many Mexicans have their own cars and drive in the city now. D. Price of cars is cheap. 3. The word “them” refers to ______________. A. cities B. problems C. jobs D. houses 4. Now, the Mexico’s population is ________. A. nearly twice as many as one in 1970. B. more than half of one in 1970. C. less than twice times in 1970. D. less than in 1970