KAPLAN OFFICIAL EXPLANATION

Four valid assumptions in the answer choices? The stem itself prepares us to expect a pretty weak argument. Our job is to locate the statement that's not assumed in the argument. The author concludes that, to achieve maximum health, Tsumi bats should be fed certain nuts and veggies and a minimum amount of fruits and berries. The evidence comes in the second sentence: These bats, who are now fed mostly fruits and berries, develop endocrine imbalances. It's not worth the effort to try to prephrase all the assumptions inherent in this argument, but if a few ideas jumped out at you, great. At the very least, you should proceed to the answer choices with a clear understanding of the evidence and conclusion.

(A) is a valid assumption. The author suggests that the bat's endocrine imbalance is a problem, and that a revised diet might fix that problem. Thus the argument does assume that bats should not be fed endocrine imbalance-producing foods.

(B) and (D) are valid assumptions too. If the proposed diet will make the bats "healthiest," then the argument assumes that it will adequately nourish them (D) and that it won't malnourish them (B). Negate these choices and the argument falls apart, confirming that these are necessary assumptions here.

An 800 test taker confirms whether a statement is a necessary assumption in an argument by seeing what happens to the argument when that statement is denied or negated. If the argument crumbles, that's proof positive that the statement is necessary and thus must be assumed.

(C) The conclusion states that the bats will be fed a minimal amount of fruits and berries, while this choice says that they will eat none. Must that be a necessary part of this argument? No, it's too extreme: The author says straight away that some fruits and berries is okay, so it need not be assumed that the bats are denied these foods altogether. (C) is therefore our winner—our "odd-man-out."

An 800 test taker reads the answer choices extremely carefully and notices even very subtle inaccuracies. Here, (C) is correct because it discusses a diet with "no" fruits or berries instead of "minimal" fruits and berries.

(E) focuses again on the author's claim that the recommended diet will make the bats healthiest. If that is true, then the author must assume that it won't create any health problems that are more detrimental to the bats' health than the endocrine imbalances that inspired the proposed diet in the first place.
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The argument can be simply stated as follows:

Tsumi bats in captivity get endocrine imbalance through diet,
They are mostly fed fruits and berries,
Therefore they should be fed primarily with nuts, grubs, vegetables

Pre-think: The assumption is that nuts, grubs, vegetables will not only prevent endocrine imbalance but also provide complete nutrition and cause no other problems (healthiest)

(A) Those who care for Tsumi bats in captivity should avoid feeding them diets that produce endocrine imbalances.
This is not an assumption. In fact, this is part of the conclusion. Correct.

(B) Tsumi bats living in captivity will not be malnourished on diets that contain minimal fruits and berries.
This is in line with the pre-think. If the Tsumi bats are malnourished with the new diet then the new diet is not the healthiest one. Incorrect.

(C) Tsumi bats living in captivity will consume diets that consist of nuts, grubs, and vegetables but no fruits or berries.
This is also in line with the pre-think. If the Tsumi bats do not eat what they are given then the intended benefits won't be realised. Incorrect.

(D) Tsumi bats living in captivity will be adequately nourished on a diet that consists primarily of nuts, grubs, and vegetables.
This is in line with the pre-think and similar to option B. If the Tsumi bats are malnourished with the new diet then the conclusion falls apart. Incorrect.

(E) For Tsumi bats living in captivity, no health problem stemming from diets consisting mostly of nuts, grubs, and vegetables would surpass in severity the health problems associated with endocrine imbalances.
This is in line with the pre-think. If the new diet causes new problems that are worse than endocrine imbalance then it is not the healthiest way. Incorrect.

Tsumi bats are a rare breed of omnivorous bat found only in highly temperate climates. Most Tsumi bats living in captivity develop endocrine imbalances from their normal zoo diets, which consist mostly of fruits and berries. The healthiest way to feed the bats, therefore, is to provide them primarily with nuts, grubs, and vegetables and only minimal amounts of fruits and berries.

Which of the statements below does NOT reflect an assumption upon which the argument depends?


(A) Those who care for Tsumi bats in captivity should avoid feeding them diets that produce endocrine imbalances. Incorrect

support argument

(B) Tsumi bats living in captivity will not be malnourished on diets that contain minimal fruits and berries. Incorrect

support argument, can be an assumption

(C) Tsumi bats living in captivity will consume diets that consist of nuts, grubs, and vegetables but no fruits or berries. Correct

contradicts with argument

(D) Tsumi bats living in captivity will be adequately nourished on a diet that consists primarily of nuts, grubs, and vegetables. Incorrect

can be an assumption

(E) For Tsumi bats living in captivity, no health problem stemming from diets consisting mostly of nuts, grubs, and vegetables would surpass in severity the health problems associated with endocrine imbalances. Incorrect

can be an assumption

IMO A

Tsumi bats are a rare breed of omnivorous bat found only in highly temperate climates. Most Tsumi bats living in captivity develop endocrine imbalances from their normal zoo diets, which consist mostly of fruits and berries. The healthiest way to feed the bats, therefore, is to provide them primarily with nuts, grubs, and vegetables and only minimal amounts of fruits and berries.

Which of the statements below does NOT reflect an assumption upon which the argument depends?

The option that does not weaken the conclusion here will be the correct answer.

(A) Those who care for Tsumi bats in captivity should avoid feeding them diets that produce endocrine imbalances.
This does not impact the conclusion in anyway, since this is already mentioned in the passage.

(B) Tsumi bats living in captivity will not be malnourished on diets that contain minimal fruits and berries.
Author mentions "only minimal amounts of fruits and berries" and mentions that nuts, grubs, and vegetables + fruits and berries are the "healthiest" option. This means that there might be less healthier options as well and that bats can thrive on the same (example, they might develop endocrine imbalances but they might not be mulnourished afterall)

(C) Tsumi bats living in captivity will consume diets that consist of nuts, grubs, and vegetables but no fruits or berries.

(D) Tsumi bats living in captivity will be adequately nourished on a diet that consists primarily of nuts, grubs, and vegetables.

(E) For Tsumi bats living in captivity, no health problem stemming from diets consisting mostly of nuts, grubs, and vegetables would surpass in severity the health problems associated with endocrine imbalances.

I'm here for the OE, I browsed through the comments before attempting and after pre-thinking it does feel like A

but i'd like to understand from the pov of the question setter


Edit: I should have stuck to my gut and chose C as I first thought before reading comments
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Conclusion: Mostly T bats living in captivity develop endocrine imbalances from their normal zoo diets, which consist mostly of fruits and berries. The healthiest way to feed the bats, therefore, is to provide them primarily with nuts, grubs, and vegetables and only minimal amounts of fruits and berries.

Prethinking: I selected assumption, T bats won't have any issue eating nuts, grubs, and vegetables.

Which of the statements below does NOT reflect an assumption upon which the argument depends?

(A) Those who care for Tsumi bats in captivity should avoid feeding them diets that produce endocrine imbalances. -> It is an assumption.

(B) Tsumi bats living in captivity will not be malnourished on diets that contain minimal fruits and berries. -> Yes, It is an assumption as per our pre-thinking.

(C) Tsumi bats living in captivity will consume diets that consist of nuts, grubs, and vegetables but no fruits or berries. -> No fruits is extreme. There is a small portion of fruit needed in T bats diets. Let's keep it.

(D) Tsumi bats living in captivity will be adequately nourished on a diet that consists primarily of nuts, grubs, and vegetables. -> Yes, T bats will be nourished with nuts, grubs, and vegetables. They have no issues.

(E) For Tsumi bats living in captivity, no health problem stemming from diets consisting mostly of nuts, grubs, and vegetables would surpass in severity the health problems associated with endocrine imbalances. -> Yes. It is another assumption.

So, It is C.

I have a question maybe someone could help with.

I hate changing around the answer choices and asking “what if”, but this question illustrates the issue perfectly.

The conclusion states “the healthiest way to feed bats” is to provide them with the diet mentioned.

Even if C used the word “minimal” instead of “no”, would C still not be a required assumption?

All the author is saying is that this is the healthiest way to feed these bats. Does he or she need to assume that the bats will actually eat the food?

In other words, you have Conclusions that say “this is what we are going to do...and I believe it will work.”

Then you have Conclusions such as this that just make a statement or general truth about something. If the bats will NOT eat the food, does that really affect whether the diet would still be considered the “healthiest way”?

I suppose it come down to the idea of what needs to be assumed for a “hypothetical” type Conclusion and one that states “this is what is going to happen.”

Any help would be appreciated (if any of the above makes sense )


I believe VeritasKarishma discussed this a few times in her posts.

Posted from my mobile device

A conclusion is not just what it says but the conviction with which it says it.

Conclusion: A must happen.
We can break the conclusion by saying that A may not happen.

Here it says that the "healthiest way is this".
So it is assuming a bunch of things including that the bats will consume a diet that consists of nuts, grubs, and vegetables and minimal fruits and berries.
But it does not assume "no fruits and berries". Hence (C) is certainly wrong.
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Thank you 🙏

I was reading too much into the question. I tend to do that after I’ve answered it (correctly or incorrectly) ....



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