CR from Kaplan's 800 GMAT book

boy141 wrote:A recent university study indicated that students who receive full scholarships tend to maintain higher grade point averages than do students who must take out loans or work to finance school. The study concluded that scholarships enable students to achieve high grade point averages by alleviating the stress related to financial concerns and freeing up students' time to study more.
The study's conclusion depends on which of the following assumptions?
(A) Students who take out loans maintain higher grade point averages than those who work to finance school.
(B) Finance-related stress affects student performance in a manner similar to that of restricted study time.
(C) Students who must work to pay for their studies cannot maintain high grade point averages.
(D) High grade point averages were not the primary criterion upon which the scholarship awards were based.
(E) Controlling stress level is less important to student performance than is intensive studying.


[spoiler](D) High grade point averages were not the primary criterion upon which the scholarship awards were based.



shoot me[/spoiler]

KapTeacherEli wrote:Sorry you're having trouble with our materials. Some of our questions can be a little tough, but that's actually a good thing--prep hard, and the real test may seem easy!

This problem looks scary, but it's actually quite formulaic. The GMAT loves cause-and-effect problems --and Kaplan will teach you to recognize and solve this type of pattern.

Whenever we see C&E, we are always dealing with one of two assumptions: A) that there is no OTHER cause, and B) that cause and effect aren't reversed. In this prompt, the author is arguing that because scholarships and grades are correlated, scholarships are the cause of good grades. For his logic to be correct, those two assumptions must be true.

So since we know exactly what he is assuming, we can predict our possible answers. First, there must be no "root" cause that leads to both grades and scholarships, such as lower tier schools having easier criteria for money and academics. Second, there must be no reversal--grades must not lead to good scholarships.

D matches our second prediction perfectly. We bubble it in and move on.