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Weaken the argument

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by thestartupguy » Sat Oct 29, 2011 12:42 pm
A drug that is highly effective in treating many types of infection can, at present, be obtained only from the bark of the ibora, a tree that is quite rare in the wild. It takes the bark of 5,000 trees to make one kilogram of the drug. It follows, therefore, that continued production of the drug must inevitably lead to the ibora's extinction.

Which of the following, if true, most seriously weakens the argument above?

(A) The drug made from ibora bark is dispensed to doctors from a central authority.
(B) The drug made from ibora bark is expensive to produce.
(C) The leaves of the ibora are used in a number of medical products.
(D) The ibora can be propagated from cuttings and grown under cultivation.
(E) The ibora generally grows in largely inaccessible places.


OA: D
Last edited by thestartupguy on Sun Oct 30, 2011 2:32 am, edited 1 time in total.
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Source: — Critical Reasoning |
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by saketk » Sat Oct 29, 2011 9:28 pm
msr4mba wrote:A drug that is highly effective in treating many types of infection can, at present, be obtained only from the bark of the ibora, a tree that is quite rare in the wild. It takes the bark of 5,000 trees to make one kilogram of the drug. It follows, therefore, that continued production of the drug must inevitably lead to the ibora's extinction.

Which of the following, if true, most seriously weakens the argument above?

(A) The drug made from ibora bark is dispensed to doctors from a central authority.
(B) The drug made from ibora bark is expensive to produce.
(C) The leaves of the ibora are used in a number of medical products.
(D) The ibora can be propagated from cuttings and grown under cultivation.
(E) The ibora generally grows in largely inaccessible places.


OA: E
Hi --

OPTION E cannot be the correct answer.

OPTION D should be the answer. Only this option is directly attacking the premise.

Kindly check the source from where you got this question.
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by avik.ch » Sat Oct 29, 2011 9:43 pm
Yes E cannot be the correct answer. The correct answer should be D.

What is the source ?
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by vaibhavgupta » Sat Oct 29, 2011 11:21 pm
msr4mba wrote:A drug that is highly effective in treating many types of infection can, at present, be obtained only from the bark of the ibora, a tree that is quite rare in the wild. It takes the bark of 5,000 trees to make one kilogram of the drug. It follows, therefore, that continued production of the drug must inevitably lead to the ibora's extinction.

Which of the following, if true, most seriously weakens the argument above?

(A) The drug made from ibora bark is dispensed to doctors from a central authority.
(B) The drug made from ibora bark is expensive to produce.
(C) The leaves of the ibora are used in a number of medical products.
(D) The ibora can be propagated from cuttings and grown under cultivation.
(E) The ibora generally grows in largely inaccessible places.


OA: E
Since, Ibora will grow in largely inaccessible places. it wont get extinct (humans cant reach it or just wont know where it is)

IMO E
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by mankey » Sun Oct 30, 2011 12:06 am
Stuck between D and E. But will go with D since this plant can be grown using its cuttings so it would not get extinct.

But dont have a strong reason to eliminate E.

Someone please help.

Thanks.
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by avik.ch » Sun Oct 30, 2011 1:05 am
mankey wrote:Stuck between D and E. But will go with D since this plant can be grown using its cuttings so it would not get extinct.

But dont have a strong reason to eliminate E.

Someone please help.

Thanks.
IN Critical Reasoning you choose the once that is "best" - even the question stem tells "most seriously weakens".

D is based on the assumption that the source of trees are finite and the trees cannot be cultivated - We cannot produce it at our own will. So D is the best - it is attacking the assumption.

Moreover the conclusion is : that continued production of the drug must inevitably lead to the ibora's extinction. - so it is already being used in spite of where it is located - yes some trees located ( "generally") in inaccessible place will be safe but that is not so strong in weakening the conclusion as D.

Hope this helps.
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by pemdas » Sun Oct 30, 2011 2:07 am
msr4mba, first of all thanks for posting this q.

this is interesting how many GMAT aspirants here make logical deductions based on simple possibility as with D ==> The ibora can be propagated from cuttings and grown under cultivation

My question: can it be or it cannot be?

feeling of logic smells wrong here as we admit one possibility but do not overturn another

choice E on the contrary is very assertive ==> The ibora generally grows in largely inaccessible places. simple as such the ibora cannot be accessed, hence must not be cut down in the wild
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by thestartupguy » Sun Oct 30, 2011 2:33 am
saketk wrote:
msr4mba wrote:A drug that is highly effective in treating many types of infection can, at present, be obtained only from the bark of the ibora, a tree that is quite rare in the wild. It takes the bark of 5,000 trees to make one kilogram of the drug. It follows, therefore, that continued production of the drug must inevitably lead to the ibora's extinction.

Which of the following, if true, most seriously weakens the argument above?

(A) The drug made from ibora bark is dispensed to doctors from a central authority.
(B) The drug made from ibora bark is expensive to produce.
(C) The leaves of the ibora are used in a number of medical products.
(D) The ibora can be propagated from cuttings and grown under cultivation.
(E) The ibora generally grows in largely inaccessible places.


OA: E
Hi --

OPTION E cannot be the correct answer.

OPTION D should be the answer. Only this option is directly attacking the premise.

Kindly check the source from where you got this question.
Sorry guys. The OA is D and not E.
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by pemdas » Sun Oct 30, 2011 2:37 am
please kindly post source of this q.
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by shikh » Wed Nov 09, 2011 11:48 pm
D is the right answer
Source: OG12
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by gunjan1208 » Thu Nov 10, 2011 12:26 am
I got D too...
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