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# Some psychologists attribute complex reasoning ability to

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Manager
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Some psychologists attribute complex reasoning ability to  [#permalink]

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23 Aug 2014, 22:31
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Difficulty:

85% (hard)

Question Stats:

55% (01:42) correct 45% (01:57) wrong based on 543 sessions

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How can we apply negation to this question to find answer quickly :

Some psychologists attribute complex reasoning ability to reptiles, claiming that simple stimulus-response explanations of some reptiles’ behaviors, such as food gathering, cannot account for the complexity of such behavior. But since experiments show that reptiles are incapable of making major alterations in their behavior, for example, when faced with significant changes in their environment, these animals must be incapable of complex reasoning.
Which one of the following is an assumption required by Sylvia’s argument?

(A) Animals could make major changes in their behavior only if they were capable of complex reasoning.
(B) Simple stimulus-response explanations can in principle account for all reptile behaviors.
(C) Reptile behavior appears more complex in the field than laboratory experiments reveal it to be.
(D) If reptiles were capable of complex reasoning, they would sometimes be able to make major changes in their behavior.
(E) Complex reasoning and responses to stimuli cannot both contribute to the same behavior

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Re: Some psychologists attribute complex reasoning ability to  [#permalink]

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23 Aug 2014, 22:52
1
reasoning offered is as follows:

premise: since experiments show that reptiles are incapable of making major alterations in their behavior, for example, when faced with significant changes in their environment

conclusion : these animals must be incapable of complex reasoning

the only way we can fill this gap between the premise and the conclusion is by assuming that : If reptiles were capable of complex reasoning, they would sometimes be able to make major changes in their behavior.

negation of D : even if If reptiles were capable of complex reasoning, they would never be able to make major changes in their behavior.---->if that is really so then it would be wrong to make conclusion that "these animals" are incapable of complex reasoning based on the fact that "these animals" did not make major changes in their behavior when they were placed in changed environment
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Re: Some psychologists attribute complex reasoning ability to  [#permalink]

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23 Aug 2014, 23:07
Some psychologists attribute complex reasoning ability to reptiles, claiming that simple stimulus-response explanations of some reptiles’ behaviors, such as food gathering, cannot account for the complexity of such behavior.
But since experiments show that reptiles are incapable of making major alterations in their behavior, for example, when faced with significant changes in their environment,
Conclusion:
these animals must be incapable of complex reasoning.

[Significant EC -> Major AB => Capable of CR].

Which one of the following is an assumption required by Sylvia’s argument?

(B) Simple stimulus-response explanations can in principle account for all reptile behaviors. [nope]
(C) Reptile behavior appears more complex in the field than laboratory experiments reveal it to be. [puts the arg in doubt.Leave it]
(E) Complex reasoning and responses to stimuli cannot both contribute to the same behavior [nope]

A Vs D:
(A) Animals could make major changes in their behavior only if they were capable of complex reasoning.
>>
1. Animals here is used in general. Whereas argument is concerned with reptiles only.
2."Only if" too restrictive, whereas argument is concerned abt some behaviors.
(D) If reptiles were capable of complex reasoning, they would sometimes be able to make major changes in their behavior.
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Re: Some psychologists attribute complex reasoning ability to  [#permalink]

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23 Aug 2014, 23:40
Thanks Aditya but i think my issue is with understanding the argument.

Some psychologists attribute complex reasoning ability to reptiles, claiming that simple stimulus-response explanations of some reptiles’ behaviors, such as food gathering, cannot account for the complexity of such behavior. But since experiments show that reptiles are incapable of making major alterations in their behavior, for example, when faced with significant changes in their environment, these animals must be incapable of complex reasoning.

Some psychologists attribute complex reasoning ability to reptiles ---- > Means that complex reasoning is because of reptiles.

simple stimulus-response explanations of some reptiles’ behaviors, such as food gathering, cannot account for the complexity of such behavior --- > Reptiles don't have complex reasoning.

But since experiments show that reptiles are incapable of making major alterations in their behavior -- > Can not alter behavior

I am not able to summarize what argument is saying.
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Some psychologists attribute complex reasoning ability to  [#permalink]

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23 Aug 2014, 23:43
let me elucidate as why A is wrong !!

A is hitting on the wrong side of the argument and it will keep doing so even if we make some changes to A

for instance if A were (modified A) : reptiles could make major changes in their certain behavior only if they were capable of complex reasoning

So now the question arise as under which argument will this modified option A serve as assumption?

Had the argument been as follows: experiments show that reptiles are capable of making major alterations in their behavior, for example, when faced with significant changes in their environment, these animals must be capable of complex reasoning. --->then the modified A would have served as an assumption
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Re: Some psychologists attribute complex reasoning ability to  [#permalink]

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23 Aug 2014, 23:54
1
oki let me deconstruct this whole labyrinthine

this whole argument is presenting some facts

fact 1: Some psychologists attribute complex reasoning ability to reptiles

supportive reasoning for fact 1 : simple stimulus-response explanations of some reptiles’ behaviors, such as food gathering, cannot account for the complexity of such behavior

evidence in support of conclusion (fact 2) : since experiments show that reptiles are incapable of making major alterations in their behavior, for example, when faced with significant changes in their environment

final conclusion: these animals must be incapable of complex reasoning
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Re: Some psychologists attribute complex reasoning ability to  [#permalink]

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07 May 2015, 16:20
1
Guys,
To make clear why D is over A, we should understand the negation of "only if" vs "if".
1) X only if Y = X implies Y --> Negation will be "if not Y, then not X".
2) X if Y = Y implies X --> Negation will be "if not X, then not Y"
Based on this, negation of option A will read as "If animals were not capable of complex reasoning, they could not make major changes in their behavior" . This does not shatter the conclusion, so A cannot be the assumption.
The maker of this question is very smart in twisting our minds
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Re: Some psychologists attribute complex reasoning ability to  [#permalink]

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04 Sep 2015, 13:26
2
Below is the official explanation from Veritas.

Solution: D

This is a Strengthen question, as demonstrated by the phrase, “which one of the following is an assumption.” Therefore, our first item of business is therefore to identify the argument’s conclusion and then look for gaps between the conclusion and the premises. The conclusion for this particular argument is at the end of the passage: “[reptiles] must be incapable of complex reasoning.” There are two clear, textual reasons why this statement is the conclusion. First, this statement uses the phrase, “must be.” This is a value judgment, one of the signs we may be dealing with a conclusion. Another reason we can pick out this conclusion in the midst of everything else is the word “since.” “Since” is a type of conclusion tag, but it attaches itself to a premise immediately next to the conclusion. Order is crucial. Thus, if we see the phrase “Since A, then B”, A is a premise supporting the conclusion, B. If we see the phrase “A, since B”, A is now the conclusion, and B is a premise undergirding that conclusion. The last sentence in the passage uses the structure, “Since A, then B.” Thus, the ending statement, “these animals must be incapable of complex reasoning,” must be the conclusion. The logical gap for this argument is not solely found in the conclusion, but in the “since” statement preceding the conclusion. As mentioned above, “since” is attached to a statement of fact required for the conclusion to be valid. However, the notion of animals being incapable of changing their behavior is not found anywhere else in the argument. The experiment supposedly implies that if an animal could demonstrate the capacity of making major behavioral changes, this would be “proof” of complex reasoning, but it leaves a large hole: could there be other possible evidences of complex reasoning besides the capacity for behavioral change? Just because there is no evidence of reptiles’ ability to make major behavioral changes doesn’t mean they can’t demonstrate complex reasoning in another manner. This is our logical gap. The correct answer must help us bridge this hole in the argument.

Answer choice “A” is a popular answer choice, but it actually fails to address the logical gap. The reason behind this is subtle, but can easily be discerned by comparing answer choice “A” to answer choice “D”. “A” tells us that the “only” possible way that an animal could have the capacity of making major changes in behavior is if the animal had a capacity for complex reasoning. In essence, major changes in behavior are “proof” of complex reasoning. However, notice that this still leaves open the possibility for other possible “evidences” of complex reasoning, without the need for demonstrating the capacity of making major changes in behavior. (Yes, demonstrating major changes in behavior is “proof” of complex reasoning, but is it the only proof? “Writing a sonnet” could be proof of complex reasoning, even if the creature never demonstrates major changes in behavior.) Thus, answer choice “A” actually reinforces the same faulty logic as that found in the experiment: “A” leaves open the possibility that reptiles could have complex reasoning in spite of not being able to show the capacity for major behavioral changes. It contains the same logical gap as the original.

Answer choice “B” is another clever trap by the Testmaker. In this case, “B” undermines the argument made by the psychologists quoted the beginning. However, undermining someone else’s argument is not the same as strengthening your own argument. The question explicitly asks us to identify the assumption in Sylvia’s argument – in other words find the statement of evidence that plugs the logical hole. Because answer choice “B” does not focus on the problem with Sylvia’s argument (in other words, it doesn’t help us bridge the gap between the capacity to make major changes and the capacity for complex reasoning), “B” cannot be the right answer.

Answer choice “C” actually undermines Sylvia’s argument. The basis for her argument is the evidence collected by a series of experiments. Because “C” claims that the results of such experiments fail to capture what is actually going on in terms of behavior, this would make any conclusions based off these experiments less solid.

Lastly, answer choice “E” also fails to address the logical gap. The hole in Sylvia’s argument is the lack of linkage between the capacity to make major behavioral changes and the capacity for complex reasoning. Answer choice “E” does not bridge this gap, but instead focuses on “responses to stimuli” – something found in the argument made by some psychologists (quoted by Sylvia at the beginning.) However, the question explicitly asks us to identify the assumption in Sylvia’s argument – in other words, we must find the statement of evidence that plugs the logical hole. Because answer choice “E” does not focus on the problem with Sylvia’s argument, “E” cannot be the right answer. It doesn’t help us bridge the gap between the capacity to make major changes and the capacity for complex reasoning.
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Re: Some psychologists attribute complex reasoning ability to  [#permalink]

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08 Oct 2015, 09:59
Some psychologists attribute complex reasoning ability to reptiles, claiming that
simple stimulus-response explanations of some reptiles’ behaviors, such as food gathering, cannot account for the complexity of such behavior.
But since experiments show that reptiles are incapable of making major alterations in their behavior,
for example,
when faced with significant changes in their environment, these animals must be incapable of complex reasoning.

Under significant changes in environment
Capability of making major alternation in behavior ===> seems to indicate Capability of complex reasoning

This is as if X then Y or X indicates Y indicating a causal argument although not directly.

This indicates 3 assumptions
1. Y does not indicate or result in X
2. X and Y are not coincidental.
3. something else does not indicate Y apart from X

Which one of the following is an assumption required by Sylvia’s argument?

(A) Animals could make major changes in their behavior only if they were capable of complex reasoning.
this negates our assumption 1

(B) Simple stimulus-response explanations can in principle account for all reptile behaviors.
This does not affect the conclusion in any way.

(C) Reptile behavior appears more complex in the field than laboratory experiments reveal it to be.
Completely out of scope as the comparison is between reptile behavior in field and lab

(D) If reptiles were capable of complex reasoning, they would sometimes be able to make major changes in their behavior.
This contains a structure of If Y is true, then X must be have been true and is correct.

(E) Complex reasoning and responses to stimuli cannot both contribute to the same behavior.
This need not be assumed and does not affect conclusion.
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Re: Some psychologists attribute complex reasoning ability to  [#permalink]

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28 Apr 2017, 19:48
When you see must - Think of conditional reasoning. as per CR bible;
Must Necessary condition -
These Animals(X changes in behavior) --- > X Conmplex resoning.

D is contra positive .
C R ---- > Changes in Behavior

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Re: Some psychologists attribute complex reasoning ability to  [#permalink]

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01 Dec 2018, 05:31
A is not the assumption because if it states a necessary condition as the only necessary condition.
The stimulus states

Reptiles are NOT modifying behaivour -> Reptiles are incapable of complex reasoning. Therefore capability of complex reasoning is a NECESSARY condition for behaviour modification but NOT the ONLY necessary condition.
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Some psychologists attribute complex reasoning ability to  [#permalink]

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01 Dec 2018, 08:05
You can simply answer this question by applying the Bridge method instead of Negation .i.e bridging the missing logic that the author has used to arrive at his conclusion

The argument concludes that Since reptiles are unable to make major alterations in their behaviour , they must be incapable of complex reasoning BECAUSE
Making major alteration is a required for having complex reasoning , so if you have complex reasoning you should be able to make major alterations
That is what D says

Hope it makes sense
Some psychologists attribute complex reasoning ability to &nbs [#permalink] 01 Dec 2018, 08:05
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