GWD一道逻辑题

Allenisland

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. Current enrollments in Kravonia’s colleges indicate that over the next four years the percentage of the Kravonian workforce with college degree will increase dramatically. Therefore, the average salary for all workers in Kravonia is likely to increase over the next four years.
Which of the following is an assumption on which the argument depends?
A.    Kravonians with more than one college degree earn more, on average, than do Kravonians with only one college degree.
B.    The percentage of Kravonians who attend college in order to earn higher salaries is higher now than it was several years ago.
C.    The higher average salary for jobs requiring a college degree is not due largely to a scarcity among the Kravonian workforce of people with a college degree.
D.    The average salary in Kravonia for jobs that do not require a college degree will not increase over the next four years.
E.    Few members of the Kravonian workforce earned their degrees in other countries.

这道题B为啥不可以？如果上大学为了找工作的人的比例比以前更低了那这些人毕业后就不一定会去工作了啊？因此工资就不会升高了嘛。。
难不成这里higher than的取非是小于等于？如果等于的话就还是会导致工资升高了罗，求nn解释

naoyixue

文中已经给出论证的原因：因为有大学文凭的人赚的比没有大学文聘的人多，而且 因接下来的4年里面读大学的人数会更多，所以接下来社会上平均工资明显很高。（此题要求假设，其实就是把文章的原因做限定，让这个原因更加稳固的能论证结论），所以如果接下来工资上升并非应为没有大学的人的工资上升而上升，（其实是排除其他原因）B的意思是上大学为了赚钱的比率现在比以前高的多。 （打个比方，想做将军的士兵的比率很多，那并非能证明将军就很多），想赚钱和最后赚钱并非直接关系。或者你想一想，现在社会上大家想转5万的人比率比以前多，那么是否因为平均工资因为这个原因上涨？明显不会，两者没有直接等号

naoyixue

其实，你只要抓住这题问的是假设，假设并非加强，加强只要一个理由就可以，假设是建立在原因和结论中的桥梁，桥梁可以使补充说明，可以使排除他因，但是总的来说桥梁就是是文中的原因成为唯一的原因，更加稳固的来证明。别慌，慢慢来，加油

Allenisland

好吧我承认我想多了，这道题就是很典型的排除他因而已吧~
B的话higher than确实不行，因为说的higher than是percentage，就算以工作为上大学目的人数与最终工作的人数是有直接联系的
但是基数变大了，percentage即使变小也有可能会导致以上大学为目的的人数增加，也就不一定会weaken掉结论了