GMAT Prep : CR 6

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GMAT Prep : CR 6

by Skywalker » Sun Oct 03, 2010 10:16 am
Why is the OA = option 1 ? Am not sure....






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by ov25 » Sun Oct 03, 2010 10:31 am
this is an inference.....to explain how would the wasp parasitize?

I would keep only three of the choices
1) it somehow knows for sure. So we can take it for granted
2) knows it by experience
3) knows it by using visual cues.

The passage says it does. So 1) over 2) and 3) as the passage would not give the source of the knowledge for the wasps

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by Skywalker » Sun Oct 03, 2010 11:29 am
Hi OV25,

Not sure I follow you ....can you please elaborate. Thanks
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by slash » Sun Oct 03, 2010 3:40 pm
I think its option C

A. This point is already discussed in the passage. "Wasps lay their eggs for any suitable size of host egg" a similar point is discussed in option A also Size of the smallest host egg is determined by wasps's egg laying behavior

B. I feel this point is out of the passage, there is no argument about effective defense against wasps

C. Passage discuss two different scenarios, when the number of eggs is less than the host egg and the other one is more than the host egg. So the conclusion should be 'Wasps learn from experience on how many eggs to be laid in host'

Any other view??

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by ov25 » Sun Oct 03, 2010 3:44 pm
Concl: wasps lay exactly the number of eggs.....in host's, suitable egg.
Premise 1: if more these eggs will die due to cause 1
Premise 2: if fewer then eggs are still destroyed due to cause 2

What does the passage suggest? or concl the passage supports?

Here it is asked of us to repeat what the passage said in other words.

A) obviously, in case of suitable egg, Wasp is successful there fore it must have known the numbers of eggs it would lay in the hosts exactly. - lets keep this contender... as the passage says it does...even if the answer had said largest, this would still be contender as the passage used 'exact' to describe the situation.

B) host insects lack defense -- out of scope, we are talking about larvae here
C) wasp knows how many eggs to lay in a host by experience - we know if know the lay the exact number but no where we are told that this is caused by experience
D) failure to lay enough eggs will be detremental to wasp - well though cause 2 accounts for this, the relative speed between laying and destroying is not suggested.
E)wasp knows how many eggs to lay using visual cues - same as C, we know the part 1 of the sentence occurs but we are not told that its visual cues guide it.

So A is the only option, though D is attractive.

Hope this helps