132. According to a study by the Carnegie Foundation for the Advancement of Teaching, companies in the United States are providing job training and general education for nearly eight million people, about equivalent to the enrollment of the nation's four-year colleges and universities.
(A) equivalent to the enrollment of
(B) the equivalent of those enrolled in
(C) equal to those who are enrolled in
(D) as many as the enrollment of
(E) as many as are enrolled in
The phrases equivalent to in A, the equivalent of in B, and equal to in C have too broad a range of meanings to be used precisely here: that is, they can suggest more than merely numerical equality. Also, as quantitative expressions, equivalent and equal often modify nouns referring to uncountable things, as in "an equivalent amount of resistance" or "a volume of water equal to Lake Michigan." To establish numerical comparability between groups with countable members, the phrase as many as is preferable. Choice D, however, uses this phrase improperly in comparing eight million people to enrollment, not to other people. The comparison in E, the best choice, is logical because people is understood as the subject of are enrolled.
关于D，enrollment 不是有入学人数的意思吗?,人数之间的比较为什么不对
关于E， as many as are enrolled in as many as 后不需要加those吗，还是省略了主语people，这样as后面是从句吗 | 
