While critics have written off the APG company’s new Model T chandelie

Actually, the negation of "If X, then Y" is "If X, MAYBE not Y." Let me give you an example:

Proposed Conditional: If you play the lottery, you will win millions of dollars.

Do you agree with this proposed conditional? Probably not! So we want to negate it. Should we say "If you play the lottery, you will NOT win millions of dollars"? Wait, that doesn't seem right. People do win the lottery; it's just not a very common outcome. If we say "It's not true that if you play the lottery, you will win millions of dollars," what we mean is "It is possible to play the lottery and NOT win millions of dollars." The proposed sufficient condition (playing the lottery) can happen without the proposed necessary condition (winning millions).

Negated Conditional: If you play the lottery, you MAY NOT win millions of dollars.

Now what about a conditional that you think is wrong in ALL cases?

Crazy Conditional: If you are in China, you are in Africa.

WHAT?!? This is clearly false and we want to negate it, but it seems funny to say "If you are in China, you MAY NOT be in Africa," right? It feels better to say "If you are in China, you ARE NOT in Africa." Of course, that is true. However, the previous version (MAY NOT) is true, too. If you ARE NOT in Africa, then you MAY NOT be there. It's this weaker version that we can commit to every time that we negate a conditional. The stronger version may be true, too, but that's always the case with negations. Consider the negation of "I love today's popular music." The negation is "I do not love today's popular music." It may be the case that I *hate* this music, but that's additional information that's not required for a negation.

So, long story short:

NOT (X --> Y) = X --> MAYBE NOT Y
or
NOT (X --> Y) = X is possible without Y
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This is what the argument says:

It is not a complete failure because it has managed to sell well in Eastern Europe.

So "selling well in Eastern Europe" is sufficient to not be a complete failure.

This is what (C) says.

(C) If a chandelier sells well in the Eastern European market, then it cannot be considered a complete failure.

That selling well in Eastern Europe is sufficient to not be a complete failure. Note that the if condition is a sufficient condition.
If A happens, then B happens - A is sufficient for B to happen.
Since our argument tells us that A happens (sell well in Eastern Europe), we can conclude that B happens (not a complete failure).
So our argument does assume (C).

Let's consider (E) now:

(E) If the Model T had not sold in good numbers in Eastern Europe, then it could have been considered a complete failure.

Note that the if condition is a sufficient condition. We know what happens if we sell well in Eastern Europe. Our argument assumes based on selling well in Eastern Europe.
But (E) talks about what could happen if A does not happen (not sell well in Eastern Europe). Does our argument depend on what happens when we do not sell well in Eastern Europe? No. We have no information on that in our argument. So this is not what is assumed by the argument.

Also note:

Given: If A, then B

Implied:
A leads to B
Not B leads to not A

Not A does not imply not B
B does not imply A

So given option (C), argument says A leads to B which is implied.
Given option (E), argument says "not A" could lead to "not B". This is not implied. So (E) is not an assumption.

If this all seems to have gotten a bit convoluted, check: https://www.gmatclub.com/forum/veritas-prep-resource-links-no-longer-available-399979.html#/2012/1 ... tatements/
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A is wrong since it didn't convey the correct opposite meaning.
B is wrong since the argument provided no information to support that.
D provided an information, true or false, is irrelevant to the argument.
E is wrong since it follows the wrong logic: "If X then Y" => "If not X then not Y".
C is correct.
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Hey Broall,
I marked option C as the OA. Just a thought. What is the negation of If X, then Y? Is it If X, then not Y.
(C) If a chandelier sells well in the Eastern European market, then it cannot be considered a complete failure.
Negation- If a chandelier sells well in the Eastern European market, then it cannot be considered a complete failure.

Correct logic is: "If X, then Y" => "If not Y, then not X"
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Hey Broall,
I agree with the logic "If X, then Y" => "If not Y, then not X. However, I was looking for the negation of option C that will destroy the argument in case of assumption.
Kindly let me know if my negation of option C is correct.
(C) If a chandelier sells well in the Eastern European market, then it cannot be considered a complete failure.
Negation- If a chandelier sells well in the Eastern European market, then it can be considered a complete failure. So, the argument weakens. Please rectify if the negation is wrong.

Yep, I think you are right.
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Please differentiate between choice A and C. How they differ from each other in meaning in context to the right answer. They both seem correct.
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VeritasKarishma : Please help with answer choice A and C. Both seem correct in logic though I marked C.
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C) If a chandelier sells well in the Eastern European market, then it cannot be considered a complete failure.
Is not C restating the premise? In an assumption question

C isn't just restating the premise. It's providing a link between the premise and the conclusion. Basically, it's saying "If (premise), then (conclusion)." This is what's known as a sufficient assumption: an assumption that, if filled in, guarantees the conclusion.
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can you please expain why A is wrong ? VeritasKarishma

Hi

Let:

X: Chandelier not selling well in the Eastern European market.
Y: Chandelier is a complete failure

Option (A) states that X --> Y (if X is true then Y is true).

The argument presented in the question stimulus states that X is false and hence Y is false, which is not necessary based on the assumption of option (A). For instance, if I state the following:

If I go out in the rain without cover (=X) then my hair will get wet (=Y).

Now, if X is known to be false (ie; I have not gone out in the rain without cover) then it is not necessary for Y to be false as well (ie; my hair is dry). When X --> Y, then Complement (X) being true does not necessarily imply Complement (Y) to be true. However, Complement (Y) being true (ie; my hair being dry) will necessarily imply Complement (X) being true (ie; I have not gone out in the rain without cover).

Another way to test whether an option presents a valid assumption or not is to negate the assumption and check the impact on the original conclusion - negation of a valid assumption should necessarily negate (or at least weaken) the original conclusion.

Here, negation of option (A) will read: If a chandelier does not sell well in the Eastern European market, then it cannot be considered a complete failure. (Please note, the negation of "being a complete failure" is "not being a complete failure" and not "being a success").

The above statement has no impact on the conclusion drawn in the question stimulus since this presents an alternate way to "not be a complete failure" which is not mutually exclusive to the reason presented in the question stimulus. Hence (A) cannot be an underlying assumption for the argument presented.

Hope this clarifies.
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Official Explanation

Answer: C

In this question, students often get confused between options A and C because they feel that the two options are saying the same thing. However, this is not the case. It is very much possible that a chandelier does not sell well in Eastern Europe but it sells in huge numbers in the rest of the world. Then it obviously cannot be considered a failure. Thus, A is not a valid assumption. C, on the other hand, has to be true if the argument has to stand.

(A) Doesn’t necessarily have to be true as explained above.

(B) The size of the Eastern European market has got nothing to do with the assumption.

(D) The range of chandeliers manufactured by the APG Company makes no difference to the assumption.

(E) This could be an inference at best but not the assumption by any stretch.
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