Cotton and BollWorms

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Cotton and BollWorms

by TwoB » Sun Jun 06, 2010 12:38 am
Plantings of cotton bioengineered to produce its own insecticide against bollworms, a major cause of crop failure, sustained little bollworm damage until this year. This year the plantings are being seriously damaged by bollworms. Bollworms, however, are not necessarily developing resistance to the cotton's insecticide. Bollworms breed on corn, and last year more corn than usual was planted throughout cotton-growing regions. So it is likely that the cotton is simply being overwhelmed by corn-bred bollworms.

In evaluating the argument, which of the following would it be most useful to establish?
A. Whether corn could be bioengineered to produce the insecticide
B. Whether plantings of cotton that does not produce the insecticide are suffering unusually extensive damage from bollworms this year
C. Whether other crops that have been bioengineered to produce their own insecticide successfully resist the pests against which the insecticide was to protect them
D. Whether plantings of bioengineered cotton are frequently damaged by insect pests other than bollworms
E. Whether there are insecticides that can be used against bollworms that have developed resistance to the insecticide produced by the bioengineered cotton
Source: — Critical Reasoning |

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by bupbebeo » Sun Jun 06, 2010 12:54 am
TwoB wrote:Plantings of cotton bioengineered to produce its own insecticide against bollworms, a major cause of crop failure, sustained little bollworm damage until this year. This year the plantings are being seriously damaged by bollworms. Bollworms, however, are not necessarily developing resistance to the cotton's insecticide. Bollworms breed on corn, and last year more corn than usual was planted throughout cotton-growing regions. So it is likely that the cotton is simply being overwhelmed by corn-bred bollworms.

In evaluating the argument, which of the following would it be most useful to establish?
A. Whether corn could be bioengineered to produce the insecticide
B. Whether plantings of cotton that does not produce the insecticide are suffering unusually extensive damage from bollworms this year
C. Whether other crops that have been bioengineered to produce their own insecticide successfully resist the pests against which the insecticide was to protect them
D. Whether plantings of bioengineered cotton are frequently damaged by insect pests other than bollworms
E. Whether there are insecticides that can be used against bollworms that have developed resistance to the insecticide produced by the bioengineered cotton[/quote

IMO: B is correct answer. this is evaluation question. so we have to use variance test.

if the answer to question in the answer choice B is YES. the conclusion is valid.

If the answer to question in the answer choice B is NO. the conclusion is not valid

So the correct answer is B.

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by TwoB » Sun Jun 06, 2010 1:10 am
@bupbebeo
Can you detail out that approach and spread it to all the options please ...
the answer is B but i am not sure how to go about such a Q.

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by ansh.kumar » Sun Jun 06, 2010 7:18 am
down to A and D, A says something ambivalence, leave it. i will go with ^D^
plz post OA

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by TwoB » Sun Jun 06, 2010 8:12 am
ansh.kumar wrote:down to A and D, A says something ambivalence, leave it. i will go with ^D^
plz post OA
OA -- B

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by kevincanspain » Sun Jun 06, 2010 8:58 am
TwoB wrote:Plantings of cotton bioengineered to produce its own insecticide against bollworms, a major cause of crop failure, sustained little bollworm damage until this year. This year the plantings are being seriously damaged by bollworms. Bollworms, however, are not necessarily developing resistance to the cotton's insecticide. Bollworms breed on corn, and last year more corn than usual was planted throughout cotton-growing regions. So it is likely that the cotton is simply being overwhelmed by corn-bred bollworms.

In evaluating the argument, which of the following would it be most useful to establish?
A. Whether corn could be bioengineered to produce the insecticide
B. Whether plantings of cotton that does not produce the insecticide are suffering unusually extensive damage from bollworms this year
C. Whether other crops that have been bioengineered to produce their own insecticide successfully resist the pests against which the insecticide was to protect them
D. Whether plantings of bioengineered cotton are frequently damaged by insect pests other than bollworms
E. Whether there are insecticides that can be used against bollworms that have developed resistance to the insecticide produced by the bioengineered cotton
First, identify the conclusion: it is likely that the genetically-engineered cotton is being overwhelmed by corn-bred bollworms instead of being attacked by bollworms that are developing resistance to the cotton's insecticide.

Evidence: More corn than usual was planted, and bollworms breed on corn.

The argument is not very convincing, as the reader is not given enough evidence to decide which of the two possible reasons for the damage (resistance or abundance of corn) is the actual reason. It may well be that both are contributing factors, nor can we be sure that there is no other factors.

Look for evidence that favors one reason over the other.

A is irrelevant
B is very helpful, for if the answer is 'yes', the corn explanation seems more plausible. If the answer is 'no', the corn explanation loses all credibility: if other cotton is not damaged to an unusual extent, then it seems unlikely that they are more worms.
C is irrelevant
D is irrelevant
E is irrelevant

I find that a lot of people have difficulty thinking about the wrong choices because they didn't REALLY understand the argument in the first place. Once you do, you see that the others are irrelevant. If you disagree, try to explain why you think that another question is critical
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by verbalfight » Sun Sep 18, 2011 4:18 am
Thanks Kevin. I have one concern though.

Issue for me with B: Although the answer is plausible, how can we assume that non bio-engineered cotton was actually present among bio-engineered cotton. The passage clearly talks about bio-engineered cotton only when it refers to 'This year the plantings'.

Isn't it out of scope..

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by dhonu121 » Sun Sep 18, 2011 11:01 pm
Hi Kevin,
In such question types:which of the following would it be most useful to establish?
If I am right, we look for choices that either strengthens or weakens the argument.(?)
From that point of view,B and D are both relevent.
If the Answer to D is yes, then the argument weakens.if the answer is No,the argument is strengthened.
How did you make D irrelevent ?
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by prsnt11 » Thu Jan 17, 2013 2:23 pm
Option D seems to be playing a trick on our autopilot that whenever we see Y -> Z in a claim we think the right answer is some other factor caused Z.
In this case, the argument is not about whether Y (Bollworms) caused Z ( cotton crop failure) , as option D suggests, but about the reason of crop failure due to Y:
1) Bollworms are resistant ( implying bioengineering solution no longer as effective...which the author does not think so but does not provide enough evidence for either)
OR
2) Bollworms are too many (implying bioengineering solution still effecive but insecticide might not be enough because the number of Bollworms is unprecedentedly high...which the author thinks so but does not provide direct evidence again)
So our job is to look for a question whose answer will serve as an evidence to support one of the reasons.
Only B provides this distinction and so is the correct answer.
Hope this helps...

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by charu_mahajan » Thu Jan 17, 2013 7:55 pm
Thanks Kevin. It all makes sense now.