Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to the following question. If you are the type of person who loves to meet many different people from different cultures and social status, then the city life is better for you. The city is where people from all different background and status come to work and live because everything is so centralized in the city. The city's population is also more concentrated, so you also have a higher chance of meeting people. In the country, the distance between other people is harder, so it is less convenient to meet other people. Hence, if you want a busy social life, the city is better. If you have asthma or you are really sensitive to pollution, then the country lifestyle is best for you. In the country there is much less pollution because there are less cars, traffic and industrial plants in the country. There are also more trees, rivers and other natural scenery. If you want your kids to run around in open and safe environment, then the country is also much better. There is much less pollution in the country than in the city because ______. A. everything is so centralized in the city B. there are much more trees in the city C. there are not as many cars in the country as in the city D. the distance between other people is harder