Student Advisor: One of our exchange students faced multiple arguments

Great explanation fluke!

This is a classic type of assumption. Anytime you are presented with an observation about two events that CORRELATE, and the conclusion makes a CAUSAL claim, it's a very good idea to check that there were not alternate models of causation that could have explained the observed phenomenon.

Remember that you're looking for a *necessary* assumption for these arguments--without that assumption being true, the argument falls apart. As gmatpassion said above, if you negate choice B the conclusion will no longer hold. That means the positive version of the answer choice must have been necessary to uphold the conclusion. In this case, the argument makes a causal claim (family problems CAUSE academic difficulties) based on the observed correlation between one student's drop in GPA and that student's family difficulties. This observation is of two events that happened at the SAME TIME. CAUSATION, however, implies that one happened BEFORE the other and LED to the other. One possible explanation of the correlation is the conclusion mentioned, but it's just as possible that the reverse model of causation was true (or that some third unknown factor caused both...for example, what if the student developed a psychological disorder that affected both relationships and GPA?)

I don't recommend defaulting to negation for all five choices because it can take some time, but if you're down to 2 answers choices and are having a hard time figuring out which is necessary and which is merely "helpful," negation is a very powerful tool. Here, if we say that the GPA decline WAS the reason for the arguments, then it's not possible for the arguments to have been the reason for the GPA decline (as the original conclusion posits). This must be our answer.

Classic case of causal reasoning.

Stated relation is not reversed that weakens the argument.
So that possibility is highlighted and avoided by option (B).

Hence , (B).

Negating B reverses the cause and effect and subsequently the argument falls flat. Answer should B.

Hi,
thanks for your helpful sulotion, but I am wondering why (C) is not correct. In this case, one of my brainstormed assuption is that "GPA can be the indicator for acedemic ability, which is the intellectual ability (is it right?)". So, when it comes to (C), it meets the assumption that GPA is the accurate measure of intellectual ability. Here, we can use the negation method. Then (C)'s negation is GPA is not the accurate measure of intellectual ability, and that clearly hurts the conclusion based on the above assumption. If GPA cannot reflect the academic ability, how can they say the lower GPA means academic difficulties? -----even stronger than (B)

Is there anything i misunderstood? Thanks for more explanation:)

Hello there , you are not following correct approach . Hope my explanation will help

Student Advisor: One of our exchange students faced multiple arguments with her parents over the course of the past year. Not surprisingly, her grade point average (GPA)over the same period showed a steep decline. This is just one example of a general truth: problematic family relationships can cause significant academic difficulties for our students.

Which of the following is an assumption underlying the general truism claimed by the Student Advisor?
(A) Last year, the exchange student reduced the amount of time spent on academic work, resulting in a lower GPA.
(B) The decline in the GPA of the. exchange student was not the reason for the student's arguments with her parents.
(C) School GPA is an accurate measure of a student's intellectual ability.
(D) If proper measures are not taken, the decline in the student's academic performance may become irreversible.
(E) Fluctuations in academic performance are typical for many students.

Conclusion here : This is just one example of a general truth: problematic family relationships can cause significant academic difficulties for our students.

assumption question requires statement that is required for the argument or conclusion to be true. So option C is irrelevant as it doesnt affect conclusion in any way whereas option B strengthens the conclusion by confirming that reason is not other way possible i.e. GPA decline is not the reason of argument .

Could someone please explain what the question about? I understood the argument fully but I got it wrong because I fail to identify the type of the question.
Thanks

This is a typical GMAT CR structure for assumption type questions. The generalisation of this structure is as follows:

Observation: A and B are seen to happen together.
Conclusion: A causes B

Assumption in the above conclusion: B does not cause A.

In the subject question,
A = Problematic family relation (argument with parents)
B = Academic difficulty (poor GPA).

in option b if you negate it doesnt it actually support the argument whereas negation should make the argument baseless.