The local agricultural official gave the fruit growers of the District

Question

Competition Mode Question

The local agricultural official gave the fruit growers of the District 10 Farmers Cooperative a new pesticide that they applied for a period of three years to their pear orchards in place of the pesticide they had formerly applied. During those three years, the proportion of pears lost to insects was significantly less than it had been during the previous three-year period. On the basis of these results, the official concluded that the new pesticide was more effective than the old pesticide, at least in the short term, in limiting the loss of certain fruit to insects.

Each of the following, if true, weakens the official’s argument EXCEPT:

(A) The amount of fruit that an orchard can potentially produce depends in part on how many mature trees it contains, and the number of mature pear trees in District 10 has declined steadily over the past eight years.

(B) During the past five years, the farmers of the District 10 Farmers’ Cooperative have been gradually implementing a variety of insect-abatement programs, and some of these programs have proven successful.

(C) Over the past five years, one of the several species of birds that typically prey on the insects that feed on pears has gradually shifted its migratory patterns, spending more and more months each year in the region that contains District 10.

(D) Some of the species of insects in District 10 that infest pear trees are water breeders, and the reservoirs and marshlands in this district have been shrinking rapidly over the past three years.

(E) The effects of certain pesticides, including the pesticide that had formerly been used in District 10, are cumulative and persist for several years after the pesticide is no longer applied.

chaitralirr · Answer

The local agricultural official gave the fruit growers of the District 10 Farmers Cooperative a new pesticide that they applied for a period of three years to their pear orchards in place of the pesticide they had formerly applied. During those three years, the proportion of pears lost to insects was significantly less than it had been during the previous three-year period. On the basis of these results, the official concluded that the new pesticide was more effective than the old pesticide, at least in the short term, in limiting the loss of certain fruit to insects.

Stimulus: the local official gave fruit growers of the district 10 a new pesticide to try for 3 years and it was found that in those 3 years the new pesticide less pears were lost to insects. On the basis of this the officials concluded that the new pesticide was more effective than old one. 
 
Each of the following, if true, weakens the official’s argument EXCEPT:

(A) The amount of fruit that an orchard can potentially produce depends in part on how many mature trees it contains, and the number of mature pear trees in District 10 has declined steadily over the past eight years.  irrelevant doesnot help to infer that the old pesticide was not better than the new one

(B) During the past five years, the farmers of the District 10 Farmers’ Cooperative have been gradually implementing a variety of insect-abatement programs, and some of these programs have proven successful.  irrelevant doesnot help to infer that the old pesticide was not better than the new one

(C) Over the past five years, one of the several species of birds that typically prey on the insects that feed on pears has gradually shifted its migratory patterns, spending more and more months each year in the region that contains District 10.  irrelevant does not help to infer that the old pesticide was not better than the new one

(D) Some of the species of insects in District 10 that infest pear trees are water breeders, and the reservoirs and marshlands in this district have been shrinking rapidly over the past three years.  irrelevant doesnot help to infer that the old pesticide was not better than the new one

(E) The effects of certain pesticides, including the pesticide that had formerly been used in District 10, are cumulative and persist for several years after the pesticide is no longer applied.
 Correct. helps to infer that the old pesticide was working with new one and so the count of pesticides was low and not because the new pesticide was better than old one

robu1 · Answer

Even though the no of mature trees is declined but output is more or loss is significantly less that means the new pesticide is more effective .hence the option A is strengthening the argument , not weakening . Therefore it is the correct answer.

Mizar18 · Answer

Option A) is the anwer because the argument is about  "the proportion of pears lost" , so we actually care about: (# of pears lost / # of total pears). This option just talks about the denominator, so we can not conclude anything with the given information.

MeBossBaby · Answer

I selected option E. 
Could you help me understand why is option E incorrect and option A correct?

Mizar18 · Answer

Conclusion:   New pesticide was more effective than the old one in limiting the loss of certain fruit

(E) vs (A) 
 
 (E)  The effects of certain pesticides, including the pesticide that had formerly been used in District 10, are cumulative and persist for several years after the pesticide is no longer applied.

This is weakening the conclusing by stating that some of the "effects" could have been from the former pesticides, so this one makes us doubt if really the new pesticide is more effective.

You can think as follows:

1) Maybe the effect of the previous pesticide + the effect of the new one made the final effect more effective, but it seems that just the second one did.
2) Maybe the effect of the previous pesticide for some reason got more effective after several years, and the second one pesticide effect was almost nil.

And you have several other possible options, but the main point is that this one attacks the assumption that the effect was entirely generated by the new pesticide.

Option (A) is correct for the reasons I stated in my previous post:

A)  is the anwer because the argument is about "the proportion of pears lost", so we actually care about: (# of pears lost / # of total pears). This option just talks about the denominator, so we can not conclude anything with the given information.

arya251294 · Answer

First, we need to understand what exactly the question is asking us.
The question is asking us to find 4 options that are weakening the argument and select the remainder (the one which is not weakening the argument)

So ideally what we want to weaken is the conclusion that " the new pesticide is better than the old one "

But, option E tells us that - the effect of the old pesticide is cumulative and still is helping in getting rid of insects, so it is possible that the new pesticide is not doing anything and the old pesticide is still doing the job, even after farmers have stopped using it or it is working in conjunction with the new one, both of which help us in weakening the conclusion that " the new pesticide is better than the old one ".

Kudos if it helped.

unraveled · Answer

The local agricultural official gave the fruit growers of the District 10 Farmers Cooperative a new pesticide that they applied for a period of three years to their pear orchards in place of the pesticide they had formerly applied. During those three years, the proportion of pears lost to insects was significantly less than it had been during the previous three-year period. On the basis of these results, the official concluded that the new pesticide was more effective than the old pesticide, at least in the short term, in limiting the loss of certain fruit to insects.

Each of the following, if true, weakens the official’s argument EXCEPT:

(A) The amount of fruit that an orchard can potentially produce depends in part on how many mature trees it contains, and the number of mature pear trees in District 10 has declined steadily over the past eight years. - CORRECT. What about the insect population?? How it is impact because of this??

(B) During the past five years, the farmers of the District 10 Farmers’ Cooperative have been gradually implementing a variety of insect-abatement programs, and some of these programs have proven successful. - WRONG. What if this particular program is included in 'some' and if not. So, it weakens and strengthens depending on the assumption we make.

(C) Over the past five years, one of the several  species of birds that typically prey on the insects  that feed on pears has  gradually shifted its migratory patterns, spending more and more months each year  in the region that contains District 10. - WRONG. Another reasons for reduction of insect population decrease.

(D) Some of the species of insects in District 10 that infest pear trees are water breeders, and the  reservoirs and marshlands in this district have been shrinking rapidly over the past three years . - WRONG. Eventually Reducing the population of species of insects.

(E)  The effects of certain pesticides, including the pesticide that had formerly been used  in District 10, are cumulative and  persist for several years after the pesticide is no longer applied . - WRONG. Weakens clearly.

Answer A.

VerbalBot · Answer

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The local agricultural official gave the fruit growers of the District

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