NN们可以解释一下这题么？谢谢！

369wendy

Of those persons who became teahers in 1968 and who later left the profession,30% today earn salaries above $35,000 a year. Of those who became teachers in 1968 and have remained in the profession, only 15% today earn salaries above $35,000 a year. These figures indicate how underpaid teachers are today.
The arguement above depend 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 outsode the teaching profession are paid.
C. 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.

这题为什么选B，不选A和C呢？

369wendy

哇~~·你太NB了~~谢谢~~·

Rebeldom

这个题目就是这个意思:
离开教师职业,结果百分之三十人NB了
不离开的,只有百分之十五的人NB了
现在说,论点是,教师职业被UNDERPAID
那要什么条件?
就是,其实这些人的能力差不多,这样才能说是UNDERPAID
否则,能力本来就有差距,收入上的差距就是必然的了,就不能得出原题结论

369wendy

啊？那B是什么意思啊？

bonnie0715

这个就跟小白鼠做实验一样的吧，AB两组可比。