In the last few years, plant scientists have been able to genetically

A – The argument is only concerned with Farmers who grow crops from genetically engineered seeds, therefore A is incorrect as it is outside of the scope of the argument.
B – This is incorrect because argument clearly states that by using genetically engineered seeds, the farmer reduces his expenditure, therefore this AC strengthens the argument.
C – Correct. This casts doubt. The author clearly hasn’t considered the additional costs of fertilizer and water in asserting (‘will’) that farmers who use the gen.modified seeds will reduce their costs.
D – Strengthens the argument as it will cost less to acquire gen. seeds therefore reducing costs.
E – This is not relevant as the argument is only concerned with farmers who are able to use the seeds. We don’t care about the other farmers.

In the last few years, plant scientists have been able to genetically engineer seeds to produce crops highly resistant to insect damage. Farmers growing crops with these seeds will be able to spend significantly less on pesticides. This cost reduction would more than make up for the higher cost of the genetically engineered seeds. Clearly, therefore, farmers who grow crops from genetically engineered seeds will be able to reduce their costs by using them.

Which of the following, if true, most weakens the argument?

A. Plant scientists have not yet developed insect-resistant strains of every crop that is currently grown commercially. -- Very broad generalization. We are only worried about the farmers who grow crops from genetically engineered seeds
B. The cost of several commonly used pesticides is expected to rise in the next few years. -- Strengthens the conclusion
C. Crops grown from the genetically engineered seeds require significantly more fertilizer and water to grow well than do crops grown from nonengineered seeds. -- CORRECT, this offsets the benefits of genetically engineered seeds by increasing the cost
D. In the future, the cost of genetically engineered seeds is likely to fall to the level of nonengineered seeds. -- Strengthens the conclusion
E. The crops that now require the greatest expenditure on pesticides are not the ones for which genetically engineered seeds will become available. -- Limited in scope to only "crops that now require the greatest expenditure on pesticides"


So, answer is C

Stimulus: B; P; P; C conclusion: farmers who grow crops from genetically engineered seeds will be able to reduce their costs by using them.
A. This isn’t in the scope of the argument
a. The conclusion focuses on the farmers who already grow these genetically engineered seeds
b. Certain crops that aren’t insect-resistant aren’t within the confines of this argument
c. Also skeptical about the insect-resistant vs. genetically engineer
i. If it’s genetically engineered, it’s highly resistant to insect damage
ii. If it’s insect resistant, is it necessarily genetically engineered?
B. The conclusion is saying that the genetically engineered seeds will be able to reduce their costs (costs that seem to come from pesticides, per the second paragraph)
a. This could potentially weaken, but come back
C. So more materials needed for these crops to grow
D. It’s not necessarily talking about the costs of the seeds themselves; it’s costs that’re reduced because of using the seeds
a. But if anything, this strengthens. If costs of the genetically engineered seeds are going to go down, this is yet another cost that’ll go down, substantiating the argument
E. This isn’t in scope of the argument
a. The conclusion focuses on the farmers who already grow these genetically engineered seeds
b. It’s already assumed that these genetically engineered seeds are being used therefore the costs are supposed to reduce; it’s irrelevant to speak to the crops that won’t have these genetically engineered seeds

C. Crops grown from the genetically engineered seeds require significantly more fertilizer and water to grow well than do crops grown from nonengineered seeds.

Lets assume genetically engineered seeds = 400 bucks + fertilizer and water (200) = 600 bucks
Non engineered seeds = 200 + fertilizer and water (100) + pesticides (350) = 650

so how can we be so sure of option c?
anything can be possible right ?

I wouldn't disagree with those numbers. However, the question is saying what "most weakens the argument." This is different from an airtight response to the stimulus that obliterates the conclusion. Out of all five answer choices, this is the best option (i.e., the option that MOST weakens the conclusion).

Hi,

For the correct answer choice C , there is no mention in the passage about the costs of Fertilizers and water. How can we assume here that the cost of fertilizer + water + GE seeds will not be profitable. Also it is mentioned in the passage that "This cost reduction would more than make up for the higher cost of the genetically engineered seeds." So isn't it safer to assume that the extra cost for fertilizers and water can still yield profit.

Coming to answer choice E , it discusses about "The crops that now require the greatest expenditure on pesticides......." . And also in the passage we are talking about crops which require pesticides - "Farmers growing crops with these seeds will be able to spend significantly less on pesticides." But if the truth is that "The crops that now require the greatest expenditure on pesticides are not the ones for which genetically engineered seeds will become available.", then there won't be any significant reduction in costs from those crops. Overall the costs for GE seeds won't be covered by the reduction of pesticide usage. Because we are talking about "...genetically engineer seeds to produce crops highly resistant to insect damage".

That is why I believe option E is a better choice than option C.

Please correct my understanding if it is wrong.

Hi,

For the correct answer choice C , there is no mention in the passage about the costs of Fertilizers and water. How can we assume here that the cost of fertilizers + water + GE seeds will not be profitable ? Also it is mentioned in the passage that "This cost reduction would more than make up for the higher cost of the genetically engineered seeds." So isn't it safer to assume that the extra cost for fertilizers and water can still yield profit.

Coming to answer choice E , it discusses about "The crops that now require the greatest expenditure on pesticides......." . And also in the passage we are talking about crops which require pesticides - "Farmers growing crops with these seeds will be able to spend significantly less on pesticides." But if the truth is that "The crops that now require the greatest expenditure on pesticides are not the ones for which genetically engineered seeds will become available.", then there won't be any significant reduction in costs from those crops. Overall, the costs for GE seeds won't be covered by the reduction of pesticide usage. Because, afterall, we are talking about "...genetically engineer seeds to produce crops highly resistant to insect damage".

That is why I believe option E is a better choice than option C.

Please correct my understanding if it is wrong.

Hi Samudra

You appear to have extrapolated the information given in the stimulus. It is true that the stimulus does not make any mention of water and fertilizer costs. However, we are not required to choose the option that leads us to the conclusion that the approach "will not be profitable" as you put it. In fact, there is nothing at all in the stimulus or the question about "profits", which is revenues less costs.

We are asked for that option which weakens the argument ie; the conclusion. The conclusion is that "farmers who grow crops from genetically engineered seeds will be able to reduce their costs by using them". Therefore, we are required to select that option which weakens this conclusion ie; that farmers using genetically engineered seeds may not be able to reduce costs. Clearly, if cost savings on pesticides makes up for increased cost of seeds, but also result in other increased costs of water and fertilizers, then the conclusion is weakened. We do not know whether it is invalidated or not, but we are not required to invalidate the conclusion.

Coming to option (E), crops requiring greatest expenditure on pesticides will not have genetically engineered seeds. However, the conclusion does not speak about these crops at all. It only states that the farmers using genetically engineered seeds, for whatever crop they are available, will be able to reduce costs. Hence option (E) does not impact the conclusion in any way.

Hope this clarifies.

From Manhattan:

Step 1: Identify the Question

The word weakens in the question stem indicates that this is a Weaken the Argument question.


Step 2: Deconstruct the Argument

Gen Eng. seeds req. less pest control

$ saved from ↑ > extra seed cost

© Gen Eng. seeds reduce crop cost for farmers


Step 3: Pause and State the Goal

On a Weaken question, the goal is to attack the logic between the premise(s) and the conclusion. In this case, the conclusion is about the overall cost of growing crops, but the premises include components of that overall cost: seeds and pesticide. Look for an answer that identifies another costly consequence of using genetically engineered seeds.



Step 4: Work from Wrong to Right

(A) This answer choice does not address the change in cost that accompanies switching to growing crops from genetically engineered seeds that are available.

(B) This answer choice presents information related to cost; however, this information supports the idea that the genetically engineered option will save farmers money. Seeds that are not genetically engineered require more pesticide, and so the costs associated with using these seeds will rise more than the costs associated with using genetically engineered seed if the cost of pesticides increases. This answer strengthens the argument.

(C) CORRECT. This answer choice identifies a cost that was overlooked in the argument. If genetically engineered seeds require more fertilizer and water than other seeds do, farmers will spend more money on this component of growing crops from genetically engineered seeds, potentially making the conclusion of the argument untrue.

(D) If the cost of genetically engineered seeds were to be reduced in the future, then farmers would have a better chance of cutting costs by growing crops from these seeds. This answer choice strengthens the argument.

(E) This answer choice centers on the irrelevant distinction between crops that have a genetically engineered seed option and those that do not. However, the conclusion is specifically about farmers who use genetically engineered seeds, and is thus only relevant for crops that do have a genetically engineered option available. Therefore, if a farmer grows a crop that requires a great expenditure on pesticides but that does not have a genetically engineered option, this particular farmer is not one of the farmers described in the conclusion, and so this choice has no bearing on the conclusion.

Hello Experts ExpertsGlobal5.

Unfortunately I cannot find explanations for why Option E) is wrong.

Could you please explain what is the reasoning behind crossing out E?

Thank you in advance

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