请阅读 Passage 1 ,完成第 21  ~ 25小题。

                               Passage 1                   

In only two decades Asian Americans have become the fastest growing U. S. minority. As their children began moving up through the nation schools,it became clear that a new class of academic achievers was emerging. Their achievements are reflected in the nation's best universities,where mathematics,science and engineering departments have taken on a decidedly Asian character. This special liking for mathematics and science is partly explained by the fact that Asian-American students whobegan their education abroad arrived in the U. S. with a solid grounding in mathematics but little or no knowledge of English. They are also influenced by the promise of a good job after college. Asians feel there will be less unfair treatment in areas like mathematics and science because they will be judged more objectively. And the return on the investment in education is more immediate in something likeengineering than wiLh an arts degree.Most Asian-American students owe their success to the influence of parents who are determined that their children take full advantage of what the American educational system has to offer. An effective measure of parental attention is homework. Asian parents spend more time with their children thanAmerican parents do,and it helps. Many researchers also believe there is something in Asian culture that makes success,such as ideals that stress family values and emphasize education.Both explanations for academic success worry Asian Americans because of fears that they feed a   typical racial image. Many can remember when Chinese,Japanese and Filipino immigrants were the victims of social isolation.lndeed,it was not until 1952 that laws were laid down giving all Asian immigrancs the right to citizenship.