Pretzels can cause cavities. Interestingly, the longer that a pretzel

Question

Pretzels can cause cavities. Interestingly, the longer that a pretzel remains in contact with the teeth when it is being eaten, the greater the likelihood that a cavity will result. What is true of pretzels in this regard is also true of caramels. Therefore, since caramels dissolve more quickly in the mouth than pretzels do, eating a caramel is less likely to result in a cavity than eating a pretzel is.

The reasoning in the argument is vulnerable to criticism on the grounds that the argument

(A) treats a correlation that holds within individual categories as thereby holding across categories as well

(B) relies on the ambiguous use of a key term

(C) makes a general claim based on particular examples that do not adequately represent the respective classes that they are each intended to represent

(D) mistakes the cause of a particular phenomenon for the effect of that phenomenon

(E) is based on premises that cannot all be true

pqhai · Accepted Answer

Because I see there's no clear answer for this question, so I want share my thought (I'm sorry I'm not CR expert). Hope it will help.

GENERAL METHOD:

This question is   Flaw in the Reasoning   question that is considered the most difficult question in GMAT. Flaw questions  appear infrequently  in GMAT. If you see this kind of question, that would be a signal you are doing very well on the GMAT.

The technique used in Flaw question is Prephrasing and Fact test. Keep in mind that answers provide "new information" always be considered wrong. 
 
 APPLY:

Now, I will prephrase the stimulus as follows:

Why eating Pretzel makes cavity? Because Pretzel contacts with teeth.   There must be  a correlation  between Pretzel and teeth  . KEY
Why eating Caramel makes cavity? Because Caramel contacts with teeth.   There must be  a correlation  between Caramel and teeth  . KEY
If No, there's no cavity 
The longer the correlations remains, the greater the likelihood that a cavity will result.

Author concludes: the correlation between Caramel & teeth lasts shorter than that between Pretzel and teeth >>>> the less likelihood that a cavity will result.

I bet you see THE GAP.   The correlation between Caramel & teeth is  DIFFERENT  from the correlation between Pretzel & teeth  . We cannot say "this is true for X also true for Y". This is wrong assumption.

What A says:  "treats a correlation that  holds  within  individual categories  as thereby  holding across  categories as well".   KEY WORD: "holds within & holding across"

It means:  Author treats a correlation between Caramel & teeth and a correlation between Pretzel & teeth the same, and thereby makes a conclusion.

A clearly shows the flaw in author's reasoning.

Takeaway:   
Flaw questions appear infrequently in GMAT. If you see this kind of question, that would be a signal you are doing very well on the GMAT.
The technique used in Flaw question is Prephrasing & Fact Test.

Hope my post helps you a little bit.

Regards.

ak_idc · Answer

Tough question. I would bet on A.

Eating Pretzels can cause cavities, and longer touch with teeth means more chances of cavities. Eating Caramels also can cause cavities, and longer touch with teeth means more chances of cavities. These are correlations in individual categories. 

Caramels dissolve more quickly in the mouth than pretzels do, does not mean that caramels are less likely to cause cavities. Because, caramels might cause cavities in the short time they are in touch with teeth. Caramels may get dissolved fast, but they may be more dangerous per unit of time compared to pretzels. 

Hence, the argument is right in relating in individual categories, but not right when comparing across categories (caramels and pretzels).

SaraiYaseenGMAT · Answer

Hi Guys, Let me know if this helps... The wording is of course very tricky and requires constant interpretation. But the important thing to take note of is that this a an argument by analogy . The conclusion that a caramel is less likely to lead to a cavity is based on the assumption that duration of contact is the only factor in developing a cavity, as is the case with the pretzel. In D, we need to 'translate' to see that this doesn't make sense: the cause: duration of contact the effect: developing a cavity In no way is the duration of contact mistaken for developing a cavity. If this helped, kindly give Kudos! :wink:

ranjeet75 · Answer

I still could not understand why A is the OA.

Also no option is looking good to answer. Experts, pl provide explanation.

What is the source of the ques

Anugmat740 · Answer

Conclusion " eating a caramel is less likely to result in a cavity than eating a pretzel is."
Author arrives this conclusion by correlation.

The Longer Pretzels remains in contact with teeth- Greater the likelihood of the cavity.

Pretzels(P) are similar to Caramels(C) in this regard.

The Lesser Caramel remains in contact with teeth lesser the likelihood of a cavity.

But the clear flaw in the reasoning is may be P and C are similar but the correlation between P and Cavity cannot be drawn accross C and Cavity.

(B) relies on the ambiguous use of a key term 
There is no ambiguous use of a key term even if we do not about terms like "cavity", "pretzels" or "Caramels" Argument can still be true. Argument does not depends on the key terms.

(C) makes a general claim based on particular examples that do not adequately represent the respective classes that they are each intended to represent 
"makes a general claim based on particular examples" - Correct a General claim that "The Lesser Caramel remains in contact with teeth lesser the likelihood of a cavity" is made as a conclusion by the author . But the second half of the sentence "do not adequately represent the respective classes that they are each intended to represent". We cannot say only these two adequately represent or does not represent the respective class. Author does not based the argument on sample size of these two.

(D) mistakes the cause of a particular phenomenon for the effect of that phenomenon 
Author Says If A occurs more frequently than likelihood of B occurrence is also more.   Here A - Pretzel contact with teeth and B- cavity 
A and C are similar.  C- Caramel contact with teeth 
Now If C occurs less frequently than likelihood of B occurrence is also less.
There is no mistake in the cause and effect, Since A and C can individually leads to more or less likelihood of B. Author argument is based on since A and C are correlated therefore likelihood of more or less B depends on this coorelation.

E) is based on premises that cannot all be true 
Keyword is  "all" . We cannot say that this all can or cannot be true. May be some part of it can be true.Also the premise in the passage is generally true, otherwise the conclusion cannot be drawn based on the premise.

(A) treats a correlation that holds within individual categories as thereby holding across categories as well 
 A - Pretzel contact with teeth, B- Cavity and C- Caramel contact with teeth 
More A causes more likelihood of B. Correlation in individual category of A
A and C are related.
Less C causes less likelihood of B. Correlation in individual category of C.
Why? A and C are similar. Author assumes what is true for "A and C" should also be true for "B and C". Author is treating a correaltion in individual category of A as holding accross individual category of C. This is the flaw in the author's reasoning.

Aryan5 · Answer

So what we are trying to do is --> pretzels and caramel are both examples quoted by the author and drawn a parallel for, now assuming that
caramel + x time --> In contact with teeth
works exactly the way as 
pretzel+ y(x>y) time --> In contact with teeth

hence, assuming pretzel = caramel which are two seperate entities, but the basic flaw/undermining assumption is both are same.
 So the correct option is A.

Hope this helps.

Raman109 · Answer

Understanding the argument - 
Pretzels can cause cavities. - Fact 
Interestingly, the longer that a pretzel remains in contact with the teeth when it is being eaten, the greater the likelihood that a cavity will result. - Fact
What is true of pretzels in this regard is also true of caramels. - Claim 
Therefore, since caramels dissolve more quickly in the mouth than pretzels do, eating a caramel is less likely to result in a cavity than eating a pretzel is. - Conclusion.

The reasoning in the argument is vulnerable to criticism on the grounds that the argument

(A) treats a correlation that holds within individual categories (longer contact of pretzels with teeth leads to cavities/caramels having less contact with teeth as they dissolve quickly) as thereby holding across categories as well (caramels cause less cavity because of less contact).

(B) relies on the ambiguous use of a key term - Out of scope.

(C) makes a general claim based on particular examples that do not adequately represent the respective classes that they are each intended to represent - out of scope.

(D) mistakes the cause of a particular phenomenon for the effect of that phenomenon - the cause is contact with teeth, and the effect is a cavity. No mistakes. Wrong.

(E) is based on premises that cannot all be true - No they can be true. Pretzels' longer contact causes cavities to be true, and caramel dissolving quickly can be true. Wrong.

VerbalBot · Answer

Hello from the GMAT Club VerbalBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.

Pretzels can cause cavities. Interestingly, the longer that a pretzel

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Critical Reasoning (CR) Questions

Pretzels can cause cavities. Interestingly, the longer that a pretzel

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards