Scientist: Cross-sections of stalactites - calcite formations deposited on cave ceilings by seeping water - can reveal annual variations in rainfall in particular areas over hundreds and thousands of years. We often found that when-according to these cross-sections-drought occurred in a particular area, it coincided with the collapse of an ancient society in that area. I hypothesize that drought reduced agricultural productivity in these areas, thereby leaving these societies without the resources needed to handle internal stresses and external threats.
Which of the following, if true, would most weaken the support for the scientist's hypothesis?
A. Many droughts indicated in the cross-sections of stalactites do not correspond with the collapse of a society in that area.
B. Information from the cross-sections of stalactites alone cannot reveal the level of agricultural output in an area at a particular time.
C. Most of the societies that collapsed during droughts did so when internal power struggles coincided with military raids from neighboring societies.
D. Most of the societies that collapsed during droughts maintained large stockpiles of food and water at the time of their collapse.
E. Information from stalactites also suggests that the collapse of some societies coincided with periods of abnormally high rainfall.
It's an interesting question that asks us to weaken the scientist's hypothesis.
What is that hypothesis? It is: drought reduced agricultural productivity in these areas, thereby leaving these societies without the resources needed to handle internal stresses and external threats.
You selected (D), which is the credited response.
But what's wrong with C and E? Answer choice (C) is what we call the opposite answer. This answer actually strengthens the hypothesis. When C says "Most of the societies that collapsed during droughts did so when internal power struggles coincided with military raids from neighboring societies" it reinforces the idea that the drought left these societies without the resources needed to handle internal stresses (aka internal power struggles) and external threats (aka military raids from neighboring societies).
What's wrong with (E)? It's out of scope. The hypothesis suggests that drought can cause the collapse of an ancient society. It never said that drought was the only cause. So information about excess rainfall and flooding does not weaken the hypothesis. This information is irrelevant to the hypothesis.
Elias Latour
Verbal Specialist @ ApexGMAT
blog.apexgmat.com
+1 (646) 736-7622
