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Explaining observed events

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by bhumika.k.shah » Fri Apr 02, 2010 4:39 am
In an experiment, subjects with uncorrected vision were asked to identify sets of letters on charts located at different distances from the subject. This experiment yielded an unexpected result. Subjects who most successfully recognized letters from all of the charts experienced much less eye muscle contraction than those subjects who could recognize letters from nearby charts only.

Which of the following best accounts for the results of this experiment?

(A) People with better vision have eye shapes better adapted to focusing on objects at different distances with minimal contraction of their eye muscles.
(B) A person's eye muscles contract less when the person is reading stationary letters than when the person is looking at moving objects.
(C) Vision-correcting glasses can allow people to recognize distant objects even if their eye muscles are unable to contract.
(D) The subjects who were most successful in recognizing letters were least likely to experience eyestrain-induced headaches.
(E) Eye muscles contract when the brain recognizes the object on which the eye is focused.


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by thephoenix » Fri Apr 02, 2010 4:52 am
IMO A
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by DanaJ » Fri Apr 02, 2010 5:08 am
I actually misread this question the first time around, which made me pick E instead of A, which is exactly the trick answer!

A is correct here: people who were good at recognizing more objects had fewer contractions of the eye. However, if a person recognizes more objects, it is also clear that he/she has better vision. This option clearly states this.

B is incorrect simply because the movement of the objects is not discussed. We are focusing on distance only.

C - while this may be true, notice that you have there in the stimulus: subjects with uncorrected vision. This basically means that the people who were subject to this experiment did not wear glasses.

D is actually a consequence and not an explanation. It's obvious that if people get fewer eye contractions, then they'd have fewer headaches. Do not confuse the consequence with the explanation, it's only a trick!

E is incorrect because it states the very opposite of what is mentioned in the passage. If the eye muscles contract when the person recognizes an object, then the people who recognized the most objects must have had the higher number of contractions. This is inconsistent with the stimulus, where we are told that these people actually had fewer contractions. You see, it's easy to get tricked by this answer choice, like I was, if you do not read the stimulus correctly (I seem to be having this problem a lot lately, since I took a GRE mock test and got three quant questions wrong simply because I misread them!).
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by gmatmachoman » Fri Apr 02, 2010 11:46 am
@Dana

What's that new GRE story?? One more 1600 on the rolls???All the best !!
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by DanaJ » Fri Apr 02, 2010 11:47 am
Haha, no... I actually took a diagnostic test last night and scored a 790 on quant and a meager 520 on verbal... Vocabulary is not really my strong point! :)
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