阅读理解。 We have known for some time that college students coming from Japan and Taiwan to study in the United States do better than their American peers(同龄人)in maths and science. These general impressions of Asian superiority(优势)in mathematics and science were proved by studies were made in the late 1960s and early 1970s. In these studies, the average score of American kindergarteners was below those from Japan. In first grade the difference increased, and by fifth grade it was very large.Moreover, 60 fifth grade classes in Japan,  Taiwan, and the United States were compared in mathematics. The average score of the highest scoring American classroom was below that of all the Japanese classrooms and all but one of the Chinese classrooms. Why is this so? Are the Asian students born smarter? A series of studies in 1986 and 1987 raised these questions, and their findings seem to point the American and Asian school systems have certain features in common. But the differences are striking. Test scores on nationwide examinations determine entry into high school and college in both Japan and Taiwan, but not in the United States. Career paths too are more closely linked to educational achievements in Japan and Taiwan. As a result, far more pressure is given to even very young children to study hard and succeed in school in both Japan and Taiwan than those in the United States. These are also striking differences in classroom instruction. By fifth grade,for example,t he U. S. children were observed to spend an average of only 19.6 hours per week in academic activities in comparison with the Taiwanese and Japanese children of 40.4 and 32.6 hours per week, respectively. What is more,the U. S.children spent less of their academic time on mathematics. By fifth grade ,the U. S.classrooms averaged 3.4 hours  per week on maths compared to 11.4 hours in Taiwan and 7.6 hours in Japan. 1. The primary purpose of this passage is to ________. A. show Asian superiority in maths and science to the American students B. compare the American educational practices with those of Asians C. warn the American government of the educational problems D. criticize the American educational system 2. Asian students in the U. S.do better in maths and science than their American peers because________. A. Americans are less interested in maths and science than Asians B. Asian students are cleverer than the American children C. Asian students spend more time in academic activities D. All of the above 3. Which of the following is NOT one of the differences between the American and the Asian school systems? ________ A. Entrance into high school does not depend on test scores on national exams in the U. S.. B. Academic achievements are more closely related to jobhunting in Asian countries. C. Children start kindergarten earlier in Asian countries than in the United States. D. Asian students pay more attention to classroom activities than Americans.