From this passage, we can learn that
A．there would be no more political and social turmoil in the U. S. without illegal immigrants.
B．the Washington government has two think tanks.
C．the government is trying to solve the issue of illegal immigration.
D．the U. S. Congress does not want to solve the issue of illegal immigration.

判断题在无法考察总体时，要从总体中抽取能代表总体的样本作为考查对象。()

未分类题Whats the reason for the decrease of the number of illegal immigrants?A．The political and social disorder in the U. S.B．American's struggling economy and the increased enforcement of immigration laws.C．Their unwillingness to do low-skilled jobs.D．The increased return migration.

未分类题The word 'cinch'(Line3, Para.1)most probably meansA．a very easy thing.B．a very complex thing.C．a great challenge.D．an extremely hard problem.

判断题数据的存储结构是数据的逻辑结构在计算机存储器上的实现，它是依赖于计算机的。()

单项选择题绝对优势理论的主要代表人物是()A、亚当.斯密B、大卫·李嘉图C、里昂惕夫D、保罗·萨缪尔森