CR: Thirty years ago, deer and elk in selected parts

[Guest]

Thirty years ago, deer and elk in selected parts of the Rocky Mountains were first discovered with a condition known as wasting disease. In 1970, two
percent of the deer and elk killed by hunters were diagnosed with the disease. In 1995, that percentage had grown to six percent. This increase in the incidence of the disease proves that wasting disease has become much more prevalent in the last twenty-five years.

If true, which one of the following selections most seriously weakens the author’s conclusion?

(A) Wasting disease has not been discovered in domestic livestock or in moose or bighorn sheep, which are also found in significant numbers in the Rocky Mountains.
(B) Wasting disease tends to make deer and elk lethargic, making them more easily killed by hunters.
(C) Since it was first reported, wasting disease has occasionally been diagnosed in deer outside the Rocky Mountains.
(D) Hunters have grown more reluctant to cooperate with the authorities in reporting their deer and elk harvest, because if wasting disease is diagnosed in their harvest, the meat will be destroyed.
(E) It is very difficult to diagnose wasting disease more than twenty-four hours after death, so many cases of the disease have gone undiagnosed.


OA: B.

I'm not et all convinced by B. This question is similar to OG-11. CR Question #17. So going by that I think A should be the answer. Please correct me if i'm wrong.

reply'll be much appreciated!

thankyou.

[esledge]

Please cite the source (author) of this problem. We cannot reply until then. If no source is cited, we will have to delete the question just to be sure we are not violating someone else's copyright. Thanks!

[Guest]

source is NOVA GMAT book.

thanks.

[esledge]

I don't agree that this one is like OG#17, which presents a general truth (bats are frightening) and a possible explanation for that truth (bats are feared only because they are active at night). The key word is "only," indicating that the GMAT writers would weaken the argument by showing some exception.

This question presents data that could legitimately be interpreted/explained two ways. Such questions on the GMAT will put forth one explanation as the conclusion. If asked to weaken, find the other possible explanation in the choices. If asked for a strengthener or necessary assumption, find a choice that eliminates the other possible explanation.

The data: the percent of hunted and killed elk that have the disease has grown.

The two possible interpretations:
1. A larger percentage of all elk have the disease, so naturally more of those killed by hunters will have the disease.
2. Diseased elk are more likely to get killed, and thus represent a larger percentage of elk killed by hunters than of elk in general.

The conclusion of this argument is approximately #1. Since (B) is approximately #2, it weakens.

Also, (A) can be rejected because it does not "most seriously" weaken the conclusion. Technically, it does not weaken the conclusion at all. It is certainly possible for wasting disease to have become much more prevalent, even if it has not been discovered in domestic livestock or in moose, bighorn sheep, or any animals other than elk. The argument told us that the rate observed in elk has risen, and (B) doesn't dispute that. You might have been assuming that if there are MANY moose or bighorn sheep, and VERY FEW elk, then (B) might weaken simply by diluting the data. If you have to assume or use the words "if" or "might" as you relate a choice to the conclusion, chances are it is not related at all.