Herbicides allow cereal crops to be grown very efficiently, with virtu

Question

Herbicides allow cereal crops to be grown very efficiently, with virtually no competition for weeds. In Britain, the 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 chick's 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 and 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

blueseas · Accepted Answer

Herbicides allow cereal crops to be grown very efficiently, with virtually no competition for weeds. In Britain, the 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 chicksâ€™ 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 and 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

conclusion :something  OTHER THAN  herbicide use must be responsible for the population decrease.

we have to weaken this means we have to show that population decrease is because of the herbicide use (and not other than herbicide use) .

option 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 chicksâ€™ diet .==>So here insects are dying because of herbicides..and insects are major part of birds diet.==>means birds are lacking in their food and because of this they are dying...===>so overall it is effect of HERBICIDES ONLY..hence it weakens==>correct

option E:The toxins contained in herbicides typically used on cereal crops can be readily identified in the tissues of animals that have ingested them ==>MEANS if somebody ingested that toxins it can be readily find in the tissues===>its stating fact====>that if you eat 5gms of toxins then it can be detected on your tissues...does this say it is poisoning birds...or what amount does this will poison bird.....so its stating a fact====and hence not affecting the conclusion.

hope it helps

automan · Answer

The author is arguing that the explanation used by environmentalists is not correct. In order to weaken the argument, evidence supporting the environmentalists' explanation must be given. A is the only answer choice that supports this explanation.

Hope to be useful for u.

desiguy · Answer

Go with A. Stimulus says that the herbicide is causing the decrease. conclusion is something else is responsible. We need a statment to weaken the conclusion.
A indirectly weakens the conclusion. Because of the herbicide, the decrease in plants is reducing the food supply for the birds.

ankurgupta03 · Answer

I think A option clearly gives us something else other than the "herbicides" which is responsible, hence is strengthening the main statement 
Need some help

plumber250 · Answer

Hi Ankur,

Let me see if I can explain again.

The thing with A, is that it's a couple of stages down from the pesticides that the effect occurs. BUT the CAUSE is still persticides:

Pesticides applied --> Weeds die --> Insects that eat weeds die ---> Partridges have nothing to eat so leave/die

So pesticides cause the lowering of partridge numbers

A is the answer

James

kinjiGC · Answer

Herbicides allow cereal crops to be grown very efficiently, with virtually no competition for weeds. In Britain, the 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?

Conclusion : There is some other reason for deaths and the reason is not pesticides.
premise : no more than trace quantities of herbicides in partridges on herbicide treated land.

Weaken.

(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.
 This option says -> Pesticides are not directly responsible but indirectly pesticides are "Responsible" hence weakens the argument

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

(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
 The argument is about the birds

(D) Birds  other than  partridges that live in and around cereal crop fields have also been suffering population declines.
Birds other than Partridges -> out of scope as we are concerned about "partridges" only.
  Tip :  if you have less time, normally "other than" is the wrong option in strengtheners and weakeners questions. Not a rule but a observation.

(E) The toxins contained in herbicides typically used on cereal crops can be readily identified in the tissues of animals that have ingested them
 Supports the argument that pesticides are not to be blamed

HKD1710 · Answer

Herbicides allow cereal crops to be grown very efficiently, with virtually no competition for weeds. In Britain, the 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?

Because Small trace of Herbicides is found in partridges so something else is the reason for population decrease.

We need to weaken this point. At least keep in mind that we need some information that tells herbicides ARE the reason for population decrease.

(B) Since partridges are valued as game birds, records of their population are more carefully kept than those for many other birds 
This data tells us that yes the population decrease that is being talked about in argument is true. But we need the information on HOW the decrease happened. Irrelevant choice. (this choice can trap those who would read the choice A and definitely will not get the logic in one go and may pick choice B because this choice looks like the one which weakens/strengthens by talking about DATA).

(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
 Crop yield is not the concern of the argument. Irrelevant choice. This is no way connected to the population decrease.

(D) Birds other than partridges that live in and around cereal crop fields have also been suffering population declines. 
If other birds have also been suffering then again we have same question about these birds as well. Did herbicides do some damage to their population. So overall this choice does not resolve the issue. Irrelevant choice. It does nothing to the said conclusion.

(E) The toxins contained in herbicides typically used on cereal crops can be readily identified in the tissues of animals that have ingested them
 It tells that the discovery of traces in partridges is true. But then the conclusion is one step ahead of the information. It can only strengthen a little bit. But for me it is irrelevant.

(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.
 
You applied Herbicides and certain weeds eliminated. Hence:

Hericides -----> certain weeds eliminated

Elimination------->reduce small insects

Reduction ------->chicks’ die of hunger (population decrease in partridges)

Hence herbicides ------->partridges population decrease

At first glance this choice would look like a strengthen-er. But this choice does weaken. The only logic here is that you don’t see cause and effect but you see cause—effect-1 (cause-1)—effect-2(cause-2)---final effect. You remember? That only initial cause and final effect matters. Hence A is correct.

Skywalker18 · Answer

Herbicides allow cereal crop 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 environmentalist claims 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.

Type- Weaken
Boil it down- something other than herbicide use must be responsible for the population decrease
Pre- Thinking - Alternate cause did not happen here or herbicides cause the population decrease indirectly .

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. Correct 
Herbicides -> weeds die -> insects that feed on those weeds die -> food source for the bird decreases
b. Since partridges are valued as game birds, records of their population are more carefully kept than those for many other birds. Irrelevant
c. Some of the weeds that are eliminated from cereal crop 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 . Irrelevant 
d. Birds other then partridges that live in or around cereal crop fields have also been suffering population declines . Irrelevant
e. The toxins contained in herbicides typically used on cereal crops can be readily identified in the tissues of animals that have ingested them. Irrelevant

Answer A

DavidTutorexamPAL · Answer

The answer is A.

We are looking to weaken the argument - that is, to argue that the herbicides  are  what is killing the birds, even though it is not found in their bodies. Therefore, it must harming them in some more  indirect  way.

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  exactly what we're looking for: an indirect causation: herbicide > less weeds > less food for birds > less birds  
b. Since partridges are valued as game birds, records of their population are more carefully kept than those for many other birds  this only strengthens the basic fact that they are indeed decreasing, not that herbicide is the cause  
c. Some of the weeds that are eliminated from cereal crop 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  irrelevant - this points out a problem with the herbicides, not related to the birds' death 
d. Birds other then partridges that live in or around cereal crop fields have also been suffering population declines  This strengthens the general correlation between bird death and crops, but not specifically between death and herbicides - maybe the alternate reasons that caused it to the partridges caused it to other birds too? 
e. The toxins contained in herbicides typically used on cereal crops can be readily identified in the tissues of animals that have ingested them  weakens - if this is the case, then the evidence that there are no toxins in their body is very strong

LoneSurvivor · Answer

I am not able to understand how A is weakening the argument ? Rather is it not strengthening the conclusion ?

Conclusion is there must be another reason for decrease instead of herbisides in A we are showing the another cause.

Please someone help.

msultania · Answer

(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 chick's diet.  (this option shows us the relation that herbicides lead to death of insects on which the bird prey, indirectly signifying that the herbicides are responsible for the decline in population)

(B) Since partridges are valued as game birds, records of their population are more carefully kept than those for many other birds (This option is out of scope and can be eliminated )

(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 (This does not help in weakening the conclusion this only tells us the relationship between the crops and the herbicides , does not show the relation between herbicide and the bird) , Hence eliminate this

(D) Birds other than partridges that live in and around cereal crop fields have also been suffering population declines. (Other birds have been suffering but the reason of their suffering is not mentioned hence can be considered as out of scope)

(E) The toxins contained in herbicides typically used on cereal crops can be readily identified in the tissues of animals that have ingested them (This in no way is weakening the conclusion because even if the herbicides can be identified, identification in itself does not lead to death)

In my opinion option A is the best answer

dcummins · Answer

The argument is that the something else, not herbicides, is responsible for the bird population decrease.

We are asked to weaken this.
 
We are essentially asked to show how the herbicide use is responsible

A does this - A tells that the herbicide use is indirectly responsible. Killing weeds > Kills food the birds eat > baby birds starve > population goes down 
B is not conducive to the argument at all. 
C doesn't effect the birds whatsoever
D this points out a general trend but does not explain why the herbicides are to blame
E this points out that the findings are accurate, but this doesn't point out why the herbicides could be to blame.

lybeaver · Answer

I have trouble understanding this statement: Tests show no more than trace quantities of herbicides in partridges on herbicide treated land. Can someone please elaborate?

dcummins · Answer

The tests show more than just a small amount of herbicides on the land where the herbicides were used.

NikhilJose · Answer

Hi,
Have a doubt. I understand none of the other answers make sense but are we not supposed to show that the decline is not due to herbicide directly. The conclusion says that something other that herbicide is causing this decrease in population.

So isn't option A strengthening that conclusion in a way. Its quite confusing.

VerbalBot · Answer

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Herbicides allow cereal crops to be grown very efficiently, with virtu

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