Q24: The Kiffer Forest Preserve, in the northernmost

LR Question 24 Explanation

QUESTION TEXT: The Kiffer Forest Preserve, in the northernmost part

QUESTION TYPE: Weaken

CONCLUSION: There will be more bears in the valley if we keep the road closed.

REASONING: There is a nature preserve within the valley. The road through the preserve has been closed for eight years. During that time, the population of bears in the preserve has increased.

ANALYSIS: Imagine this as two circles. There is a big circle labelled “valley”. Inside that, there is a smaller circle labelled “preserve”.

The road in the preserve has been closed, and the population of bears in the preserve has increased. Where did those bears come from?

The argument is assuming the bears came from outside the valley. But what if the bears just moved from the big circle (the valley) into the little circle (the preserve). In that case, the road hasn’t increased the population of bears: it has just moved them from the rest of the valley into the preserve.

Two of the answers say “only some”. That implies a minimum and a maximum on a range, such as, say 2%–98%. It’s not exactly like the word “some”, which can go all the way to all.

___________

This is a trap. You might have picked this if you thought “maybe the bears moved from the valley into the preserve”. But for that prephrase, E is a better answer.
The bears could have migrated from the valley, but this answer is also consistent with migration from outside the valley. We have to take answers at their least helpful.
This strengthens the argument. It shows some of the new bears in the preserve have come from outside the valley.
This strengthens the argument. It shows that at least some of the new bears have come from outside the valley.
This sounds like my prephrase, but it’s not strong enough. This answer is consistent with the following situation.
- Then: 20,000 in the valley outside the preserve. 1000 in the preserve.
- Now: 19,999 in the valley outside the preserve. 30,000 in the preserve.
CORRECT. If this is true, then it sounds like bears are just moving from other parts of the valley into the preserve. There has been no actual increase inside the valley as a whole.