Nutritionists are advising people to eat more fish, since the omega-3

Plan suggests that aquaculture cause the decrease in the consumption of wild fish or this plan will not cause decrease in the current fish population in the wild.

Above is the assumption.

Choice D clearly states that aquaculture needs the wild fish as feed for farmed fish.

Thus D is the answer

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Eat fish = Combat diseases Problem : There is not enough in the oceans and lakes ( If people start consuming fish ) fish due to overfishing Solution : To ease pressure on wild fish ----> Increase consumption of farmed fish.

(D) Clearly calls into question the solution...

If feed for Farmed fish is made from the small wild-caught fish then the pressure on wild fish is not reduced and hence weakens the conclusion.

Hence the answer will clearly be (D)

We are looking for something to weaken the theory : "The obvious method to ease the pressure on wild fish populations is for people to increase their consumption of farmed fish"

Option D is the only one that talks about the fact the wild fish would still keep decreasing as they are the main food for the farmed fishes.

There are 2 assumption that say the pressure on wild fish will not be reduced.
first is that the amount of omega even after increasing the consumption is not sufficient to match the needs for omega of wild. Therefore go to wild.
The second is as mentioned in statement D. Which is weakened.
AC D is correct.

straight with D.
Merged topics!

D is the correct choice - Suggests the increasing consumption of farmed fish would require increased use of wild fish as feed for farmed fish and therefore would not ease pressure on wild fish populations.

Nutritionists are advising people to eat more fish, since the omega-3 fatty acids in fish help combat many diseases. If everyone took this advice, however, there would not be enough fish in oceans, rivers, and lakes to supply the demand; the oceans are already being overfished. The obvious method to ease the pressure on wild fish populations is for people to increase their consumption of farmed fish.

Which of the following, if true, raises the most serious doubt concerning the prospects for success of the solution proposed above?

Mostly all the weaken the argument questions attacks the conclusion so, it’s very important to isolate the conclusion, it makes things easier.

COnclusion: Ease the pressure on wild fish populations is for people to increase their consumption of farmed fish.
Assumption: That this plan will get it's success and that consumtion of farmed fish is not going to impact the wild fish poplulation.


(A) Aquaculture, or fish farming, raises more fish in a given volume of water than are generally present in the wild.
Out of scope.

(B) Some fish farming, particularly of shrimp and other shellfish, takes places in enclosures in the ocean.
Out of scope.

(C) There are large expanses of ocean waters that do not contain enough nutrients to support substantial fish populations.
Not a weakner

(D) The feed for farmed ocean fish is largely made from small wild-caught fish, including the young of many popular food species.
That means farmed ocean fish feeds on small wild fish. This is certainly a weaakner because it has a negative impact on the conclusion.

(E) Some of the species that are now farmed extensively were not commonly eaten when they were only available in the wild.
Again it has no impact on the conclusion of the argument.

Which of the following, if true, raises the most serious doubt concerning the prospects for success of the solution proposed above?

Our main CONCLUSION is that people increase consumption of farm fish so as to reduce the pressure on wild fish population.
We have to weaken the conclusion by selecting an answer choice which states the idea that consumption of wild fish population cannot be reduced and consequently the pressure from wild fish shall not be released

(A) Aquaculture, or fish farming, raises more fish in a given volume of water than are generally present in the wild.- Out of Scope answer choice

(B) Some fish farming, particularly of shrimp and other shellfish, takes places in enclosures in the ocean. Out of Scope answer choice

(C) There are large expanses of ocean waters that do not contain enough nutrients to support substantial fish populations. This is a strengthener answer choice as it supports going for farm fish population instead of wild fish hence not a weakener

(D) The feed for farmed ocean fish is largely made from small wild-caught fish, including the young of many popular food species.
CORRECT, a weakener answer choice as if feed for farm fish is made from wild fish it would directly affect wild fish population
(E) Some of the species that are now farmed extensively were not commonly eaten when they were only available in the wild.- Incorrect as this answer choice strengthens the conclusion

IMO D - If the feed for farm fish is made from small wild-caught fish it would directly affect wild fish population. The goal was to save wild fish! This would weaken the argument completely.

Conclusion: to ease pressure on the wild fish population, people should eat more farmed fish.

If we want to weaken this conclusion, we're looking for an answer choice that shows eating more farmed fish would not be beneficial for the wild fish population. (Or may even be harmful.)

D - The feed for farmed ocean fish is largely made from small wild-caught fish, including the young of many popular food species.--- shows that farmed fish require wild fish as food. Thus, when people eat more farmed fish, more wild fish will be required to feed the farmed fish, depleting the very wild fish populations the plan was intended to spare.

The conclusion the author wants us to believe: The obvious method to ease the pressure on wild fish populations is for people to increase their consumption of farmed fish.

If the farmed fish growth depend on wild fish caught this will not ease the pressure. This is exactly what answer choice D says.

D is the correct answer choice as it clearly sites the reason that why the pressure from wild fish cannot be reduced.


Hope this helps. Kudos if you find this helpful ?

The author concludes that:-

"The pressure on wild fish will be reduced if people increase consumption of farmed fish"

Given :- 1)Nutritionist are advising people to eat more fish.
2)Omega 3 in fish fights disease.
3)If everyone starts eating more fish there won't be enough fish in the ocean,rivers and lakes.
4)The oceans are already over fished.
Here the author assumes the following:-

Assumption :- The pressure on the wild fish will be reduced if people start consuming farm fish.Consuming farm fish will have no affect on the no. of fish in the ocean,rivers and lakes.

Possible weakener:- The statement which states that farm fishing will have effect on the number of fishes in the wild.

Option analysis:-
(A) Aquaculture, or fish farming, raises more fish in a given volume of water than are generally present in the wild.-acts as a strengthener instead

(B) Some fish farming, particularly of shrimp and other shellfish, takes places in enclosures in the ocean.irrelevant to the conclusion

(C) There are large expanses of ocean waters that do not contain enough nutrients to support substantial fish populations.whether the certain portion contains nutrients or not has no effect on whether the farm fishing will ease effect from fish in the wild

(D) The feed for farmed ocean fish is largely made from small wild-caught fish, including the young of many popular food species.-in line with our weakener. Hence correct

(E) Some of the species that are now farmed extensively were not commonly eaten when they were only available in the wild- irrelevant

Hi everyone,

After I read this problem, answer choice (D) immediately stuck out to me as the correct answer. That said, I've been trying to get into the habit of finding 4 wrongs answers instead of 1 right one and so I wanted to comment on why the answer choice (E) is out of the running.

I understand why answer choices (A), (B) and (C) are incorrect; however, I can't completely justify why (E) is incorrect.



To weaken the conclusion, we need a statement that suggests that farming fish would not relieve the consumption demand of wild-caught fish. Answer choice (E) states that some of the species that are framed a lot weren't commonly eaten (i.e. in demand) when only wild-caught. When I'm considering answer choice (E), stand alone, it seems the statement does confirm that the demand on wild-caught fish would not be relieved. It's only when I compare it to the relative strength of answer choice (D) that I'm able to eliminate it.

GMATNinja is there any chance that you might be able to respond?

We want to know what happens when we start farming a wild species that is already in demand (i.e. in demand before farming starts). (E) only tells us about species that were not in demand before farming started! So this example is not relevant to the wild fish example. (Mmm... fish.)

I hope that helps a bit!

Hi GMATNinja,

How can we say that they are talking about 'fish already in demand' because the paragraph just mentions 'farmed fish' ?'
If the farmed fish is not according to people's demand then they wont eat the farmed fish and the pressure on the wild fish wont be relieved.

Please let me know what am I missing

The author's goal is to "ease the pressure on wild fish populations," and the solution that he/she proposes to reach this goal is "for people to increase their consumption of farmed fish."

So, we need to cast doubt on the argument that if people do increase their consumption of farmed fish, the pressure on wild fish populations will be eased.

(E) states that some fish that were not commonly eaten when only available from the wild are now farmed extensively. This doesn't particularly impact the author's argument, because we have no idea why the fish were not popular before they were farmed, or why they are popular now. Maybe they were not commonly eaten because they were exceedingly rare, or difficult to catch, or some other reason. The author's reasoning depends on increased consumption of farmed fish reducing pressure on wild fish, and the exact break down of which species are more commonly eaten when farmed, and why that is the case, is irrelevant.

Even if you read (E) to imply that people will be reluctant to eat farmed fish, this does not cast doubt on the author's plan -- regardless of people's preferences, the author is arguing for them to suck it up and eat farmed fish. We need to cast doubt on the idea that if people do, in fact, increase their consumption of farmed fish, pressure on wild fish populations will be reduced.

Compare (E) with (D):

Here, people could follow the author's plan perfectly (eating only farmed fish), and yet there would still be pressure on wild fish populations, because the young of many wild-caught fish will die in the process.

This casts doubt on the idea that increasing consumption of farmed fish will ease the pressure on wild fish populations.

I hope that helps!