PT 32, October 2000, Section 1, Question 12, Weaken Question

Samcandoit!

I was struggling with the correct answer (B) and (E). Obviously, (B) is correct, because it points out the assumption that the route that polar bear went is already familiar to them, therefore, it does not meet the criteria (definition) of "navigation". However, I think (E) also points out that "polar bears rely on their extreme sensitivity to smell in order to scent out familiar territory", while in the contextual information, it has been pointed out that Navigation is defined as (1) animal's ability to find its way from unfamiliar territory to points familiar to the animal (2) but beyond the immediate range of the animal's senses. (E) points out the assumption that it is in the range of the animal's sense, because polar bears' extreme sensitivity to smell; therefore weaken the argument.
I saw couple people were struggling with this answer choice for the same reason, could someone help us? I will really appreciate.

Dr. Yamata

Good question. The stim defines navigation as "the animal's ability to find its way from unfamiliar territory to points familiar to the animal but beyond the immediate range of the animal's senses."

The evidence the naturalists hold up is an example of a polar bear that returned home after being released at some distant point.

Comparing B to E, I find E to be not specific enough. Polar bears OFTEN rely on (yada yada yada) ehh.. this right away signals that this is a weak answer choice, and wouldn't weaken the argument that much. Of course, there could be some correct answers with OFTEN (some) as the quantifier, but if that were case I'd probably be looking for an ALL or NEVER in the stim. And, in fact, in this particular question, an OFTEN doesn't really cast much doubt upon the evidence. It could still be that the polar bears in this particular case don't often do such and such a thing.

B, however, hits the evidence square in the nuts. It says the polar bear was released somewhere on its annual migration route. Hmm. Annual migration routes seem like they would be very familiar to the polar bear. The evidence states that navigation involves animals finding their way from unfamiliar territory. If B were true, how would this evidence be relevant? B does exactly what the question asks, which is "cast doubt upon he validity of the evidence." And since the question is looking for the MOST doubt, it is correct. E is just not strong enough.

Ask more questions please.