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

Take a look at this post for a more thorough discussion of option (E).

One key element at play here is the author's exact conclusion: "The obvious method to ease the pressure on wild fish populations is for people to increase their consumption of farmed fish."

The author isn't arguing that people are likely to eat farmed fish, or that there is a demand to eat farmed fish. Instead, the author is saying that IF people increase their consumption of farmed fish, THEN the pressure on wild fish populations will be eased.

So, people don't have to like eating farmed fish -- what people prefer is irrelevant to the author's conclusion. Regardless of current or past demand for farmed fish, the author's argument would hold -- IF everyone held their noses and ate farmed fish, THEN the pressure on wild populations would be eased.

It's clear that (E) doesn't raise any serious doubts about the author's plan, so it can be safely eliminated.

I hope that helps!

nightblade354 eakabuah MentorTutoring VeritasKarishma

Am I falling into circular reasoning fallacy with approach mentioned towards the end?



(As per passage; There is no conclusion, hence no argument is presented.)
Cause:
increase farmed fish (FF) consumption
Effect:
reduce pressure on wild fish (WF) consumption



I could understand that (D) says: If the food itself for FF is WF then WF population is going to be reduced, hence my conclusion that supply for WF shall be sufficient in future shall fall apart.

BUT, what about below situation?
If FF feeds on WF, but people eat more FF then the less FF will CAUSE more WF in oceans and other places.

Sometimes, I cut off wrong choices easily, but spend more time to FIT correct ans to place.

Problem: Not enough wild fish in oceans to handle increased consumption.
Plan: People should eat more farmed fish.

We need to weaken the plan. We need to find the option that suggests that the plan may not work.

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

Good for our plan. We will be able to raise more fish per volume of water so farmed fish should be able to support increased demand.

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

Irrelevant.

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

We already know that we don't have enough wild fish.

(D) The feed for farmed ocean fish is largely made from small wild-caught fish, including the young of many popular food species.

This says that increase in farmed fish will decrease wild fish population especially the young. This puts our plan in question. The wild fish population will suffer a lot if the new generation is wiped. Hence, this weakens our plan. We don't need to establish that the plan will definitely not work. We just need to doubt the plan. So we do not need to consider further "what if" scenarios. More information could have positive or negative impact on the plan - it doesn't matter. We only need to see how this information impacts our plan.

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

Irrelevant

Answer (D)

Hello, adkikani. I think VeritasKarishma has provided a fine analysis of the question above, so I will not reiterate. Speaking to your approach, any time you find yourself bending over backwards to argue against a reasonable answer, just move on and see whether any other answer touches on the main points and fits better. You do not have to make an on-the-spot determination. In many cases, you will find that you do less work for the correct answer after eliminating obviously incorrect options. The problem with your situation, as you called it above, is that you are not taking into account what is already taken for granted in the passage, that the oceans are already being overfished. So if, to use your reasoning above, [people] eat less FF, we CANNOT say that this action will CAUSE more WF in oceans and other places. People, apparently, are going to eat their fish, one way or another. Whether they eat wild-caught fish directly or indirectly, the problem of overfishing would not have been rectified.

Good luck with your studies.

- Andrew

Conclusion: “The obvious method to ease the pressure on wild fish populations is for people to increase their consumption of farmed fish.”
Prethink: what if they don’t actually consume these farmed fish because it tastes different than that of wild fish? What if they use wild fish to feed farmed fish?

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

(A) Aquaculture, or fish farming, raises more fish in a given volume of water than are generally present in the wild.
Strengthener, if anything. This is a plus for why farmed fish is better than wild fish.

(B) Some fish farming, particularly of shrimp and other shellfish, takes places in enclosures in the ocean.
Neutral answer – this does nothing. It doesn’t matter WHERE they have the fish farming, so long as they actually take pressure off the wild fish. But this doesn’t shed light on if it’s going to divert wild fish consumption to farmed fish consumption.

(C) There are large expanses of ocean waters that do not contain enough nutrients to support substantial fish populations.
Strengthener if anything. This is a reason why you should use wild fish, so more the reason to use farm fishing.

(D) The feed for farmed ocean fish is largely made from small wild-caught fish, including the young of many popular food species.
So to have the farmed fish you need to take wild fish? This sounds like a circular cycle that doesn’t produce any results. There’s no reason to raise farmed fish, if you could potentially kill wild fish in equal numbers (maybe even more). Doesn’t necessarily mean this could be the case, but this definitely casts doubt on the potential results of the conclusion. Moreover, this option addresses a key element: “…the young of many popular food species.” This means that a younger generation may be made into feed, so in the long term, the population of ocean fish would really be under pressure. Honestly just glanced over this part of the answer choice, but TY VeritasKarishma

(E) Some of the species that are now farmed extensively were not commonly eaten when they were only available in the wild.
This changes nothing. A subset of fish that weren’t eaten in the wild are not being farmed (and presumably, not eaten now). What about all the other fish? The conclusion is worried about the oceans being overfished for (presumably) the fish that are going to be eaten.

Great explanation! Thanks.
In brief, if the plan is A====>B, we shouldn't doubt on A. What we need is to attack the logic link from A to B.

For Aquaculture feeding of the fish is necessary but if the feed is produced from the ocean's supply of fish, which are already rare or failing to fulfill the supply then the fish farming will be in trouble.
The answer is D.

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