CONFUSING CR: To avoid economic collapse, Russia must

[Guest]

To avoid economic collapse, Russia must increase its GNP by 20%. However, due to the structure of its economy, if the 20% threshold is reached, then a 40% increase in GNP is achievable.

Assuming that the above statements are true, which one of the following must also be true?

(A) If ethnic strife continues in Russia, then a 20% increase in GNP will be unattainable.
(B) If a 40% increase in Russia’s GNP is impossible, its economy will collapse.
(C) If Russia’s GNP increases by 40%, its economy will not collapse.
(D) If the 20% threshold is reached, then a 40% increase in GNP is achievable and a 60% increase is probable.
(E) If Russia’s economy collapses, then it will not have increased its GNP by 40%.

IMO: C.

what should be the answer?

thanks

[RonPurewal]

please post the source of this question. without knowing the source, we can't answer the question, and we'll eventually have to delete it.

thanks.

[Guest]

Source is Nova gmat preparation book.

thanks.

[JonathanSchneider]

The correct answer here is actually B. This is a bit tricky. A sample diagram:

to avoid collapse, need 20% increase
if 20% increase ---> 40% increase possible

Now, note B: if a 40% increase is impossible, then this must mean that a 20% increase is ALSO impossible (if the 20% were possible, the 40% would be as well). AND if that 20% increase is impossible, then the economy will collapse.

C may be tempting, but it is wrong. While we are told that a 20% increase is necessary to avoid collapse, such an increase does not assure that we will avoid collapse - it is only one requirement. There may be other things that we need to avoid collapse.