A、China. B、India. C、Japan. D、Mexico. A短文中提到，在美国的K—12学习计划中，中国人是最大的国际群体。故选A。

In the 1970s, a typical Chinese student in the U. S. was there for a master’s or doctoral degree. They were then followed by students pursuing undergraduate degrees. (17)Now, Chinese are the largest international group in US kindergarten-through-12th grade, or K-12, programs of study. November statistics show that 34,578 Chinese students were studying in primary and secondary schools in the US, or 52 percent of all international students there. Five years ago, the number was 8,857, according to The Wall Street Journal. It cited statistics from the Student and Exchange Visitor Program, a Department of Homeland Security unit that tracks foreigners in the US on student visas and the schools they attend. (16) At The Brook Hill School in Bullard, Texas, the number of Chinese students grew from six to 20 in the past six years, the maximum allowed from one foreign nation. (18) One of the reasons for many Chinese students studying in US schools is to escape the gaokao, China’s national entrance examination, and the fierce competition that comes with it. The other motivation is to get prepared for US colleges. " More younger Chinese students choose to go to US high schools, as more parents believe that this leads to a better education if their kids finally choose to go to US universities and colleges," said Yu Haoyang, founder of Global Intellect Consulting in Beijing. "They believe that US high schools offer better English-language and cultural training, and it is easier for their kids to master these skills and become more competitive," she said.
16. What do we learn about the passage?
17. Which foreign country has the most students in US K-12 programs of study?
18. Which is not a reason for Chinese students to study in the US?