求助大全-Ⅱ-13

wstjy

大全-Ⅱ-13.    Of those person who became teachers in 1968 and who later left the profession, 30 percent today earn salaries above $35,000 a year: of those who became teachers in 1968 and have remained in the profession, only 15 percent today earn salaries above $35,000 a year. These figures indicate how underpaid teachers are today.
The argument above depends on which of the following assumptions about the persons for whom statistics are cited?
(A) At least one-third of the group of persons who have remained in teaching would today be earning more than $35,000 a year if they had left teaching.
(B) The group of persons who left teaching and the group who did not are comparable in terms of factors that determine how much people outside the teaching profession are paid.
(C) Most of those persons who left teaching did so entirely because of the low salaries teachers earn.
(D) As a group, those persons who have remained in teaching are abler and more dedicated than the group of persons who left teaching.
(E) The group of persons who left teaching and who today earn more than $35,000 a year were more capable teachers than the group who remained in the profession.

答案是B 可是具体B是什么意思呢，不能理解？忘指点，谢谢！

wstjy

NN快来指点指点我吧！

LittleMike

题干的逻辑顺序是这样的：1968年有两拨人，都是老师，一拨在现在不做老师了，另一拨还在做老师，然后说不做了的基本上赚钱更多，由此想得到结论：教师这个行业underpay

B说的就是经济学里面经常提到的'other things being equal'，B本身翻译过来是说留下的和离开的人在非教师职业中决定受多少pay的因素相似，也就是说那帮留下的人要是出去做了也能像出去的人那样赚钱更多，那么就是能够证明老师这个行业确实underpay

wstjy

OOoo终于看明白了，结构好复杂的说~感谢！感谢！