BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Question from MBA.com preptest 2

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 167
Joined: Tue Feb 26, 2008 4:37 am
Thanked: 5 times
Followed by:1 members

Question from MBA.com preptest 2

by pranavc » Wed Jul 16, 2008 7:39 pm
1. Herbicides allow cereal crops to be grown very efficiently, with virtually no competition from weeds. In Britain, partridge populations have been steadily decreasing since herbicide use became widespread. Some environmentalists claim that these birds, which live in and around cereal crop fields, are being poisoned by the herbicides. However, tests show no more than trace quantities of herbicides in partridges on herbicide-treated land. Therefore, something other than herbicide use must be responsible for the population decrease.

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

(A) The elimination of certain weeds from cereal crop fields has reduced the population of the small insects that live on those weeds and that form a major part of partridge chicks' diet.

(B) Since partridges are valued as game birds, records of their population are more carefully kept than those for many other birds.

(C) Some of the weeds that are eliminated from cereal crop fields by herbicides are much smaller than the crop plants themselves and would have no negative effect on crop yield if they were allowed to grow.

(D) Birds other than partridges that live in or around cereal crop fields have also been suffering population declines.

(E) The toxins contained in herbicides typically used on cereal crops can be readily identified in the tissues of animals that have ingested them.

Any input will be appreciated. Thank you.
Top
Source: — Critical Reasoning |
Master | Next Rank: 500 Posts
Posts: 340
Joined: Thu Jun 12, 2008 8:09 am
Location: India
Thanked: 6 times

Re: Question from MBA.com preptest 2

by kiranlegend » Wed Jul 16, 2008 8:21 pm
pranavc wrote:1. Herbicides allow cereal crops to be grown very efficiently, with virtually no competition from weeds. In Britain, partridge populations have been steadily decreasing since herbicide use became widespread. Some environmentalists claim that these birds, which live in and around cereal crop fields, are being poisoned by the herbicides. However, tests show no more than trace quantities of herbicides in partridges on herbicide-treated land. Therefore, something other than herbicide use must be responsible for the population decrease.

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

(A) The elimination of certain weeds from cereal crop fields has reduced the population of the small insects that live on those weeds and that form a major part of partridge chicks' diet.

(B) Since partridges are valued as game birds, records of their population are more carefully kept than those for many other birds.

(C) Some of the weeds that are eliminated from cereal crop fields by herbicides are much smaller than the crop plants themselves and would have no negative effect on crop yield if they were allowed to grow.

(D) Birds other than partridges that live in or around cereal crop fields have also been suffering population declines.

(E) The toxins contained in herbicides typically used on cereal crops can be readily identified in the tissues of animals that have ingested them.

Any input will be appreciated. Thank you.
IMO A.. A tells that the reduction in bird population is due to fewer or no weeds
Top
Master | Next Rank: 500 Posts
Posts: 267
Joined: Wed Jul 16, 2008 12:20 am
Thanked: 4 times
Followed by:1 members

by Mani_mba » Wed Jul 16, 2008 8:41 pm
E seems to be best to me.Here is my reasoning..

B,C and D looks irrelevant to me.

The remaining A and E are the choices to be deeply analyzed. We have to counter the conclusion "Something other than herbicide use must be responsible for the population decrease." that bases on the evidence " tests show no more than trace quantities of herbicides in partridges on herbicide-treated land"

"A" seems to be very vague which says that Herbicides are indirectly responsible for the population decrease.

In my opinion, we have to support that "herbicide toxins are responsible for the population decrease" by attacking the quailty of medical test done.
In E, it says that "Toxins of herbicides can be readily found in the tissues of animals that have ingested them".

Any other suggestions please.....
Top
GMAT Instructor
Posts: 83
Joined: Sun Mar 02, 2008 9:05 pm
Thanked: 21 times
Followed by:2 members

by rey.fernandez » Wed Jul 16, 2008 9:39 pm
Option E tells us that if, in fact, the birds were ingesting the herbicides, we would be able to determine that easily via tests. In other words, it SUPPORTS the argument by saying that the tests are reliable: we can confidently say that the birds are not ingesting the herbicide, because if they were, we'd be able to tell, therefore something else must be killing them off.

I'd say pick option A. It shows that the herbicide is ultimately the reason for the bird's population decrease. If the herbicide were not being used, the birds' food supply would not be threatened, and the birds themselves would not be threatened.
Rey Fernandez
Instructor
Manhattan GMAT
Top
Legendary Member
Posts: 1159
Joined: Wed Apr 16, 2008 10:35 pm
Thanked: 56 times

by raunekk » Wed Jul 16, 2008 10:36 pm
IMO:E..


"A" supports the conclusion..

Thanks..
Top
Master | Next Rank: 500 Posts
Posts: 340
Joined: Thu Jun 12, 2008 8:09 am
Location: India
Thanked: 6 times

by kiranlegend » Thu Jul 17, 2008 7:38 pm
raunekk wrote:IMO:E..


"A" supports the conclusion..

Thanks..
mate, can you give us your explanation too? also as to why A supports the conclusion 'something other than herbicide use must be responsible for the population decrease.
'? :shock:

to the question onwer: please post the OA now.
Top
Senior | Next Rank: 100 Posts
Posts: 76
Joined: Mon Jun 30, 2008 4:31 am
Location: India
Thanked: 2 times

by Aldiablo » Fri Jul 18, 2008 12:11 am
IMO A.
When you think you can or you cannot, you are generally correct.
Top
Master | Next Rank: 500 Posts
Posts: 167
Joined: Tue Feb 26, 2008 4:37 am
Thanked: 5 times
Followed by:1 members

by pranavc » Fri Jul 18, 2008 2:31 am
I posted the question and the OA is A. Here is the deal though. I felt like D was also pretty close. A makes sense after a lot of analysis (which I probably won't have time for on the actual test). Any clues as to why D is wrong? Yes, I understand that it talks about birds other than partridges BUT it definitely reaffirms the fact that the herbicides are a significant cause of the population decline.

Any thoughts on this? I am curious as to the basis in which D was eliminated.

Thanks in advance.
Top
Senior | Next Rank: 100 Posts
Posts: 36
Joined: Mon Mar 17, 2008 5:23 am
Thanked: 1 times

by bigfernhead » Fri Jul 18, 2008 6:09 am
The reason I believe is because of scope.

The scope here is partridge. Not all birds are partridge. The effect on one bird cannot be assumed for another.
Top
Master | Next Rank: 500 Posts
Posts: 401
Joined: Fri May 04, 2007 9:21 am
Thanked: 3 times
Followed by:1 members

by NSNguyen » Fri Jul 18, 2008 7:01 am
A, weaken,
B, C, D out of scope
E strengthen
:lol:
Please share your idea and your reasoning :D
https://bmnmed.com/home/
https://nguyensinguyen.vietnam21.org
Top
Master | Next Rank: 500 Posts
Posts: 167
Joined: Tue Feb 26, 2008 4:37 am
Thanked: 5 times
Followed by:1 members

by pranavc » Sat Jul 19, 2008 10:44 am
I suppose the "out of scope" explanation for D is a fair one. Thank you.
Top
Legendary Member
Posts: 1161
Joined: Mon May 12, 2008 2:52 am
Location: Sydney
Thanked: 23 times
Followed by:1 members

by mehravikas » Tue Jan 19, 2010 12:08 pm
@Testluv,

Need your help on this one. I got this question on the gmat prep. The conclusion is that "something other than the use of herbicide must be responsible for the population decrease"

How is the answer A???? I am just not able to understand. Don't you think E is a better choice.

Thanks,

Vikas Mehra
Top
GMAT Instructor
Posts: 1302
Joined: Mon Oct 19, 2009 2:13 pm
Location: Toronto
Thanked: 539 times
Followed by:164 members
GMAT Score:800

by Testluv » Tue Jan 19, 2010 2:32 pm
Hi Vikas,

on this one, you have to be careful characterizing the conclusion; he's not necessarily dismissing the herbicides themselves as an explanation for the population decrease...You'll notice the language of the conclusion is that herbicide USE isn't causing the population decrease.

So, we can weaken this argument by finding a choice that suggests that usage of the herbicides is causing the population decrease.

Looking at choice A: it talks about how eliminating weeds reduces the population of insects that the partridges eat. And we know from the passage that the usage of these herbicides eliminates weeds. So that would suggest that usage of the herbicides may well be responsible for the decrease of the partridge population.

This one may have been tricky because the way choice A weakens the argument has nothing to do with the partridges being poisoned as was the author's line of reasoning. This is okay though because of the way the author wrote his conclusion: "...something other than herbicide use must be responsible...". So, choice A makes less likely the conclusion that something other than herbicide use was responsible for this population decrease.

Choice E talks about ease of identification. But that was never a problem. We know from the stimulus that "tests show no more than trace quantities..." and the stimulus never indicates that there was a design flaw in any of these tests. So the idea that the tests were accurate is part of the author's evidence. In assumption family questions, you should avoid choices that tend to restate (or contradict) evidence.

But even if you didn't see that choice E was restating evidence, you could eliminate it on the basis that it strengthens rather than weakens the argument.
Kaplan Teacher in Toronto
Top
Legendary Member
Posts: 1161
Joined: Mon May 12, 2008 2:52 am
Location: Sydney
Thanked: 23 times
Followed by:1 members

by mehravikas » Tue Jan 19, 2010 3:35 pm
This is indeed a tricky problem. After going through your explanation I read the argument again. The first line of the argument states that herbicides eliminates weeds, the language in somewhat confusing -

"Herbicides allow cereal crops to be grown very efficiently, with virtually no competition from weeds."
Testluv wrote:Hi Vikas,

on this one, you have to be careful characterizing the conclusion; he's not necessarily dismissing the herbicides themselves as an explanation for the population decrease...You'll notice the language of the conclusion is that herbicide USE isn't causing the population decrease.

So, we can weaken this argument by finding a choice that suggests that usage of the herbicides is causing the population decrease.

Looking at choice A: it talks about how eliminating weeds reduces the population of insects that the partridges eat. And we know from the passage that the usage of these herbicides eliminates weeds. So that would suggest that usage of the herbicides may well be responsible for the decrease of the partridge population.

This one may have been tricky because the way choice A weakens the argument has nothing to do with the partridges being poisoned as was the author's line of reasoning. This is okay though because of the way the author wrote his conclusion: "...something other than herbicide use must be responsible...". So, choice A makes less likely the conclusion that something other than herbicide use was responsible for this population decrease.

Choice E talks about ease of identification. But that was never a problem. We know from the stimulus that "tests show no more than trace quantities..." and the stimulus never indicates that there was a design flaw in any of these tests. So the idea that the tests were accurate is part of the author's evidence. In assumption family questions, you should avoid choices that tend to restate (or contradict) evidence.

But even if you didn't see that choice E was restating evidence, you could eliminate it on the basis that it strengthens rather than weakens the argument.
Top
GMAT Instructor
Posts: 1302
Joined: Mon Oct 19, 2009 2:13 pm
Location: Toronto
Thanked: 539 times
Followed by:164 members
GMAT Score:800

by Testluv » Tue Jan 19, 2010 4:49 pm
"Herbicides allow cereal crops to be grown very efficiently, with virtually no competition from weeds."
Yeah, so the way herbicides allow crops to grow is by killing off surrounding weeds that compete for resources (such as sunlight, soil nutrients, etc). In CR, you are not expected to use outside knowledge but they will expect you have to have good vocabulary. Knowing that herbicides kill plants helps us to understand that sentence. (We know "cide" means kill as in "homicidal" or "suicidal".)
Kaplan Teacher in Toronto
Top
Post new topic Post Reply