Self-study
Support The Kiffer Forest Preserve, in the northernmost part of the Abbimac Valley, is where most of the bears in the valley reside. ██████ ███ █████ █████ ████ ███ ████ ████ ███████ ███ ████████ ███ ████ ██████ ███ ██████████ ████ ██████████ ███ ██████ ████████ █████ ███ ████████ ████ ██████████ ████ ████████ ██ ███ ████ ██ ████ ███████
Summarize Argument: Phenomenon-Hypothesis
The author concludes that the valley’s bear population will increase if the road that runs through the preserve (which is a part of the valley) is kept closed. This is because during the past eight years, during which that road has been closed, the preserve’s bear population has nearly doubled.
Notable Assumptions
The author assumes that there has been an increase in the valley’s bear population over the eight years the road has been closed. (There’s a difference between the preserve’s population increasing and the valley’s population increasing.) The author also assumes that the closing of the road over the last eight years was the cause of the increase in the preserve’s bear population.
24.
Which one of the following, ██ █████ ████ ██████████ ███ █████████
a
Most of the ████████ ██ ███ ██████████ ████ ██████████ ████ ███ ████ █████ █████ ██ ███ ██ ██████████
Even if most of the increase is due to migration, this migration can still involve bears who were originally outside the valley. So, this doesn’t undermine the assumption that the valley bear population increased.
Unwarranted assumption
Unwarranted assumption
b
Only some of ███ ████████ ██ ███ ██████████ ████ ██████████ ████ ███ ████ █████ █████ ██ ███ ██ █████████ ██ █████ ████ █████ █████ ██ ███ ███████ ███████
This strengthens by establishing that only some, but not all, of the increase in the preserve’s bear population is from bears in the valley. This means some of the increase comes from bears outside the valley, which supports the assumption that the valley’s population increased.
Directionally wrong
Directionally wrong
Answers that, if they have any effect, do the opposite of what we want (weaken when we're trying to strengthen, or strengthen when we're trying to weaken).
c
Only some of ███ ████████ ██ ███ ██████████ ████ ██████████ ████ ███ ████ █████ █████ ██ ███ ██ █████████ ██ █████ ████ ███████ ███ ███████ ███████
This strengthens by establishing that at least some of the increase in the preserve’s bear population is from bears outside the valley. This supports the assumption that the valley’s population did experience an increase during the eight years.
Directionally wrong
Directionally wrong
Answers that, if they have any effect, do the opposite of what we want (weaken when we're trying to strengthen, or strengthen when we're trying to weaken).
d
The bear population ██ █████ ██ ███ ███████ ██████ ███████ ███ ██████ ██████ ████████ ███ █████████ ████ ███ ████ █████ ██████
This answer is consistent with an increase in overall valley bear population. The population in the valley outside the preserve may have decreased, but the increase within the preserve might still outweigh that decrease, indicating some bears came from outside the valley.
Unwarranted assumption
Unwarranted assumption
e
The bear population ██ ███ ███████ ██████ ███ ████████ █████ ███ ████ ████ ███ ████ █████ ██████
This undermines the assumption that the valley’s population increased during the eight years. (E) establishes that the increase in the preserve’s population comes entirely from movement of bears from other parts of the valley.
Alternate explanation
Alternate explanation
Weaken: Introduce or support an alternate explanation for a phenomenon.
Strengthen: Helps to eliminate an alternate explanation for a phenomenon.