The growing popularity of biofuel has caused a greater percentage of

Question

The growing popularity of biofuel has caused a greater percentage of farmland to be devoted to corn rather than soybeans, the other major crop. A pesticide manufacturer argues that this transition has led to an increase in soybean aphids, a pest that damages soy crops and reduces soybean yield, but does not live on corn. The manufacturer attributes the increase to the reduced acreage of soy crop, which translates into fewer habitats for the insects that prey on the soy aphid.

The pesticide manufacturer's argument makes which of the following assumptions?

A. The insects that prey on the soy aphid do not prey on any other species.
B. Soybean aphids cannot be killed by traditional pesticides.
C. The larger the amount of farmland devoted to soybeans, the more important it is that soy aphids are eliminated.
D. The proximity of a soybean crop to a corn crop has little effect on the presence of soy aphids.
E. The decrease in available habitats more seriously affects the insects that prey on the soy aphid than the soy aphid itself.

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ajay0520 · Answer

manufacturer is basically saying, reduced acerage for soyabean caused reduced habitat for insect that eats aphids resulting into increase in aphids.
  so here the assumption must be that the reduced area for soyabean didn't affect aphids as much as they affect the insects that feeds on them.

option E  gets the job done.

Dereno · Answer

The pesticide manufacturer's argument claims that the increase in soybean aphids is due to the reduction in soybean acreage, which results in fewer habitats for the insects that prey on soybean aphids. For this argument to hold, the assumption must be that the reduced soybean acreage harms the predators of soybean aphids more than it harms the aphids themselves.

Let's look at each option:

A. The insects that prey on the soy aphid do not prey on any other species.
This is not an assumption necessary for the argument. The argument focuses on the predators of soy aphids needing habitats, not whether they prey on other species.
B. Soybean aphids cannot be killed by traditional pesticides.
This is irrelevant to the argument. The manufacturer’s claim is about habitat reduction affecting predator populations, not the effectiveness of pesticides.
C. The larger the amount of farmland devoted to soybeans, the more important it is that soy aphids are eliminated.
This is also irrelevant. The argument is about the relationship between the amount of farmland for soybeans and the predators of aphids, not the need to eliminate aphids.
D. The proximity of a soybean crop to a corn crop has little effect on the presence of soy aphids.
This would be relevant if the argument was trying to link corn to aphid presence. However, the manufacturer is attributing the rise in aphids to the reduction in soybean crops, not proximity to corn. Thus, it is not an assumption made by the argument.
E.  The decrease in available habitats more seriously affects the insects that prey on the soy aphid than the soy aphid itself. 
This is the key assumption. The pesticide manufacturer's argument hinges on the idea that reducing the number of soy fields harms the predators of soy aphids more than it harms the aphids, leading to an increase in aphid populations.
The  correct answer is E.

Bunuel · Answer

Official explanation:

This is an Assumption question. The argument asserts that, because of reduced acreage devoted to soy crops, soy aphids — pests that prey on the soy crop —have increased because there are fewer habitats for the aphids' predators. In other words, because there are fewer habitats for the predators, it is assumed there are fewer predators, leaving more aphids, despite the fact that there are fewer habitats for the aphids, too. Consider each choice, looking for some version of that unstated assumption.

In choice (A), the strong language ('any other') is too extreme; the argument would still be valid if there were other soy pests that these predators preyed on.

Choice (B) is incorrect because traditional pesticides are outside the scope of the argument.

Choice (C) suggests that as soy crops decrease, it's less important that aphids are eliminated. This doesn't directly relate, however, to whatever underlies the claim that aphids have increased.

Proximity to a corn crop, as given in choice (D), is off-topic. Focus on what happens purely within the soy crop.

In order for the argument to stand, it must be correct that the smaller number of habitats has more of an effect on the predator than on the aphid itself. If this weren't the case, there would be just as few aphids.  Therefore, choice (E) is correct.

The growing popularity of biofuel has caused a greater percentage of

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The growing popularity of biofuel has caused a greater percentage of

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