A good Inference question guyzzz...

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Vervet monkeys use different alarm calls to warn each other of nearby predators, depending on whether the danger comes from land or from the air.

Which one of the following, if true, contributes most to an explanation of the behavior of vervet monkeys described above?

A. By varying the pitch of its alarm call, a vervet monkey can indicate the number of predators approaching.

B. Different land-based predators are responsible for different numbers of vervet monkey deaths.

C. No predators that pose a danger to vervet monkeys can attack both from land and from the air.

D. Vervet monkeys avoid land-based predators by climbing trees but avoid predation from the air by diving intofoliage.

E. Certain land-based predators feed only on vervet monkeys, whereas every predator that attacks vervet monkeys from the air feeds on many different animals.



The OA is D.

According to me, this is an inference question or after reading the options you could also say that the question is inference cum example question.

I got the answer as D. Try this it is a good question. May be from the OG:
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by ranjeet75 » Thu May 10, 2012 4:12 am
It is [spoiler]D[/spoiler], because monkeys are using different alarm calls so that they can understand how to save themselves - by climbing or by diving intofoliage.

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by confuse mind » Thu May 10, 2012 4:44 am
Can someone please explain me why C is not correct?

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by hariharan3112 » Thu May 10, 2012 8:50 am
Yes i would go with a c as well...Thats coz the question here is not what the monkey eventually does to avoid being predated but it uses different sounds for different attackes..and both the attacks are not inter-related..

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by ice_rush » Thu May 10, 2012 9:09 am
(D) it is for me. Try negating (C) and you'd see that the argument would not make sense -- Only (D) explains why these monkeys use different alarm calls to alert them of danger from land or air.

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by Bill@VeritasPrep » Thu May 10, 2012 9:24 am
An attack can't come from both land and air at the same time, so a predator being able to do both (at separate times) is irrelevant. The monkeys can still use the appropriate call for each attack.
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by vk_vinayak » Fri May 11, 2012 1:46 am
@Bill

Can you tell me what does the question ask us to do in this argument?
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by Bill@VeritasPrep » Fri May 11, 2012 7:07 am
"Which one of the following, if true, contributes most to an explanation of the behavior of vervet monkeys described above?"

We have two key terms in the question stem. Whenever the GMAT tells us to accept something as true ("if true"), the statement it refers to is a premise. In this case, "which of the following if true" means that all of the answer choices are premises, so we're adding a piece of evidence to an existing argument. This narrows down our possible question types to Strengthen, Weaken, and Explain the Paradox (the only question types where the answers are premises).

The stem asks us to add evidence to an explain the behavior of the monkeys. We can treat that behavior as the end result of our evidence; which statement makes that behavior make sense? Thus, I would treat it as a Strengthen question.
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by veenu08 » Mon Jun 17, 2013 11:54 pm
I have doubt in C and D-

C- There can be a possibility that a predator can attack from land or air, so detecting the nature becomes tough.. So to make the argument valid isn't it that we rule out such scenario?

D- Vervet monkeys avoid land-based predators by climbing trees but avoid predation from the air by diving into foliage. Isn't climbing the trees and diving into foliage very specific, when no such info is given in argument.

Can someone please explain me the two.