根据选项和题目是否相关，把除B以外的所有选项都干掉。
A 原文没有提多于一个大学学历的事情
C原文没提Kravonia与其他国家比较
D原文没提雇主提供一个岗位之前是没大学学历现在是大学学历的人干
E同样原文没提
通过这个思路我根本就没完全琢磨明白B是个啥意思，但是我粗略看感觉说的和原文是相关的事情，于是选B
-- by 会员 limingdaili (2011/10/27 18:39:47)
In Kravonia, the average salary for jobs requiring a college degree has always been higher than the average salary for jobs that do not require a degree. Over the last few years, the number of Kravonians enrolled in college has been growing steadily. Therefore, who have at least the qualification of a college degree will eventually be significantly higher than it has been over the last few years.
Which of the following, if true, most seriously weakens the argument?
A. Kravonians with more than one college degree earn little more, on average, than do Kravonians with only one college degree.
B. The average number of years Kravonian college students remain enrolled before completing a degree has been increasing over the past several years.
C. Despite the increase in the number of Kravonians attending college, the percentage of the population attending college is lower in Kravonia than in most other countries.
D. In recent years, employers have been requiring college degrees for workers in jobs that were previously performed successfully by Kravonians who did not have college degrees.
E. For many years, employers in Kravonia have had difficulty finding enough college graduates to fill the high-paying jobs that were available.
有没有好心的童鞋解释解释正确答案 ，选B。。。Thanks!!
-- by 会员 疯愁怂狗子 (2011/10/27 17:54:41)