Twenty years ago, in order to rid Katarina Island from the menace of a

Question

Twenty years ago, in order to rid Katarina Island of the menace of an insect larva X that was destroying rice crops, a special caterpillar-eating bird Y was introduced to the island. Now, however, overconsumption of fruits by the enormous Y population menaces many of the island’s fauna. Agriculturists plan to reduce Y’s population by using a chemical spray, which has caused devastating epidemics in Y’s population. However, there is a small chance of this chemical infecting the native Katarinian grey hornbill, an endangered fruit-eating bird. The agriculturists’ plan, therefore, is protective of agricultural interests in terms of controlling fruit consumption on the one hand but will increase the danger to native bird populations on the other.

The argument above assumes which of the following?

A. It is possible to reduce Y’s population without causing any danger to the Katarinian grey hornbill.

B. None of the birds or animals in Katarina prey on the bird Y.

C. In places where the chemical was used, the populations of bird Y were successfully controlled.

D. The use of the chemical can be controlled in a manner that will not completely wipe out the bird Y population on the island.

E. The enormous Y population is not a bigger threat to the Katarinian grey hornbill than the chemical spray.

mavrck0102 · Accepted Answer

Question Type: Assumption Question

Conclusion: The agriculturists’ plan is protective of agricultural interests in terms of controlling fruit consumption on the one hand but will increase the danger to native bird populations on the other.

Premise: In order to rid of X, Y was introduced. 
Y overconsumes fruit, harming fauna of katrina island.
To rid of Y, agriculturist plan to use a chemical spary which might infect Katarinian Hornbil.

Lets evaluate our options:
A. This options seems to weaken the conclusion. Our job is to find the assumption not to weaken it. Eliminate it.

B. Lets negate this option. then we get, " some  birds or animals in Katarina prey on bird Y". If there are some birds or animals that prey on bird Y, then agriculturist can increase the population of those certain birds and animals to control the population of bird Y, and hence the conclusion weakens bcoz the new plan will work but will not increase danger to native bird population. Keep option B for now.

C. This option gives us reason to believe why spraying the chemical will work as planned. This option strengthens the argument imo. Hence, eliminate.

D. This option tells us that the chemical can be used in a way such that population of bird Y is not wiped out, but notice it says nothing about spary's effect on the native bird population. Hence, the conclusion still stands. Hence, eliminate.

E. Lets negate this option. "The enormous Y population  is a bigger threat to  the Katarinian grey hornbill than the chemical spray". This weakens the conclusion, because if Y population is a bigger threat to the Katarinian grey hornbill, then by using the chemical spray the agriculturist are actually decreasing the danger to the native bird population(katarinian hornbill). Keep.

Between B&E, i would pick E because while not assuming B does weaken the conclusion but we dont know the effect of those birds and animal on the katarinian hornbill. While assuming not assuming E directly weakens the conclusion.

CattoSiddy · Answer

Hi  AndrewN !

Option (C) seems like a logical assumption & correlates & strengthens the conclusion we're arriving at i.e. the chemical spray will work as expected & will help control bird Y's population. Is it because it doesn't have any mention of the impact on the native Katarinian grey hornbill population that it isn't the right answer?

Can you please help explain? TIA!! :")

TheBipedalHorse · Answer

Population of Y, or what happens to Y, is not something that bothers the author too much. Author says that while fruits will be protected because of the agriculturists' plan, it will end up harming the native birds of K.

Also note that Y is not a native bird of K. Y was introduced to K.

Only option E connects agriculturists' plan to population of native birds. Author is assuming that native birds of K are not under threat from increasing population of Y.

Taulark1 · Answer

In places where the chemical was used, the populations of bird Y were successfully controlled.
negating this - in some places where chemical was used, populations of bird y were not succesfully controlled.
so it doesn't have to be that all the places where the chemical was used , there had to be success. even if some places had success and some didn't argument still stands as is

DmitryFarberMPrep · Answer

D is not the answer. The argument doesn't depend on keeping some of species Y alive. That might be helpful in controlling caterpillars, but the conclusion is just about preventing overconsumption of fruit and threatening native species, neither of which depend on keeping any Y alive.

gowthami21

Please explain d is the answer

A_Nishith · Answer

Argument Analysis: 
 Premise 1:  The Y population is overconsuming fruits, threatening the island’s fauna.
 Premise 2:  A chemical spray that devastates Y has a small chance of infecting the endangered Katarinian grey hornbill.
 Conclusion:  The agriculturists' plan balances protecting agriculture and increasing the risk to native birds.

Required Assumption: 
The assumption bridges the gap between the proposed plan and its justification, ensuring that the plan does not cause a greater problem than the one it intends to solve. Let’s evaluate each option:

Option A: It is possible to reduce Y’s population without causing any danger to the Katarinian grey hornbill.
Analysis: This is not required. The argument acknowledges the risk to the hornbill but proceeds with the plan regardless. The agriculturists are aware of the risk but still justify the plan as balancing interests.

Option B: None of the birds or animals in Katarina prey on the bird Y.
Analysis: Irrelevant. The argument does not rely on whether Y has predators, but rather on the trade-off between controlling Y and the risk to the hornbill.

Option C: In places where the chemical was used, the populations of bird Y were successfully controlled.
Analysis: This could support the efficacy of the chemical but is not an assumption. The argument does not question the chemical’s ability to control Y but focuses on the potential harm to the hornbill.

Option D: The use of the chemical can be controlled in a manner that will not completely wipe out the bird Y population on the island.
Analysis: This is unnecessary. The agriculturists’ plan is to reduce Y’s population, not eradicate it entirely. There’s no indication that wiping out Y is a concern in the argument.

Option E: The enormous Y population is not a bigger threat to the Katarinian grey hornbill than the chemical spray.
Analysis: Correct.  If the Y population were a bigger threat to the hornbill than the chemical, the plan might inadvertently harm the hornbill population more by leaving Y uncontrolled. This assumption is necessary to justify the agriculturists’ balancing act between agricultural interests and the risk to native birds. 
 Correct Answer: E

VerbalBot · Answer

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Twenty years ago, in order to rid Katarina Island from the menace of a

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