阅读理解。 If you were to come up with a list of organizations whose failures had done the most damage to the American economy in recent years, you would probably have to start with the Wall Street firms that brought us the financial crisis. From there, you might move on to the automakers in Detroit. But I would suggest that the list should also include a less obvious nominee: public education. At its top level, the American system of higher education may be the best in the world. Yet in terms of its core mission-turning teenagers into educated college graduates-much of the system is failing. The United States does a good job enrolling (招生) teenagers in college, but only half of the students who enroll end up with a bachelor's degree. So identifying the causes of the college dropout crisis in the world's largest economy matters enormously, and a new book called 'Crossing the Finish Line' tries to do precisely that. Its authors are economists William Bowen and Michael McPherson, and a doctoral candidate Matthew Chingos. The first problem they diagnose is something they call under-matching. It refers to students who choose not to attend the best college they can get into. They instead go to a less selective one, perhaps one that is closer to home or less expensive. About half of the low-income students with a grade-point average of at least 3.5 in high school and an SAT score of at least 1,200 do not attend the best college they could have. 'I was really astonished by the degree to which well-qualified students from poor families under-matched,' said Mr. Bowen. In fact, well-off students attend the colleges that do the best job of producing graduates. Meanwhile, lower-income students-even when they are better qualified-often go to colleges that excel (擅长) in producing drop-outs. 'It's really a waste,' Mr. Bowen said, 'and a big problem for the country.' As the authors point out, the only way to lift the college graduation rate significantly is to lift it among poor and working-class students. Instead, it appears to have fallen. What can be done? Money is clearly part of the answer. 1. Which of the following would people first think of as a factor responsible for the American financial crisis according to this passage? A. The government. B. Public education. C. The Detroit automakers. D. The Wall Street firms. 2. What is a big problem with American higher education? A. It is hard to enroll enough students into college. B. Many colleges are experiencing low rate of graduation. C. Many college students stay away from classes. D. It is hard for many colleges to get financial aid from the government. 3. Why do some students under-match? A. Because they have financial difficulty. B. Because they face ambition crisis. C. Because they lack confidence. D. Because they can't get guidance. 4. The passage is mainly about _______. A. problems with secondary American education and possible solutions B. America's financial crisis, its cause and influence C. low rate of American college graduation, its cause and its influence D. relationship between American education and its economy