- Thu Jan 12, 2017 1:31 pm
#32051
Complete Question Explanation
Strengthen. The correct answer choice is (E)
This is an excellent example of a "defender" Strengthen question and a good illustration of the manner in which Strengthen questions can add an additional layer of complexity to what might have otherwise been easier Weaken questions. In the stimulus, the editorial concludes that postponing the beginning of high school could reduce car accidents involving teenagers. The premises offered include (1) the fact that teenagers have a biological mechanism that causes them to sleep later, (2) are sleepy if woken up too early, and (3) this sleepiness can impair driving ability. Finally, as evidence the editorial cites (4) the results of a change in Granville's high school schedule: When Granville moved the start time back to 8:30, teenage accidents declined.
Since the editorial attempts to establish a causal link between Granville's change and the decline in accidents, as a prephrase, you should anticipate an answer that likely mitigates one of the many possible causal flaw weaknesses. In other words, in this scenario, as an initial step, you should consider all the ways one might WEAKEN this causal conclusion. The likely defender credited response will mitigate one (or more) of these issues.
Answer choice (A): This choice attempts to muddle the issue by making a contrast between teenagers and young children. The reasoning behind this incorrect response might be that test-takers could conclude that an earlier school start time for younger children might be appropriate, but such a start time is inappropriate for teenagers. As it stands, this answer choice is irrelevant and does nothing to link the causal connection between later start times and fewer accidents.
Answer choice (B): This choice again tries to sidestep the issue in the scenario by providing a different kind of reason why delaying the start of high school in the morning might be a good idea. This answer choice is based on a misreading of the conclusion, i.e. it is based on the misunderstanding that the editorial is primarily concerned with advocating for a later school start time instead of attempting to show a link between the later start time and a reduction in accidents involving teenagers.
Answer choice (C): This answer choice actually weakens the conclusion by providing evidence that a delay in high school start time may not have the impact the editorial supposes since many teenagers who work would be unaffected by such a delay. Presumably, these other teenagers will continue to need to be at work at the same time regardless of what high schools do.
Answer choice (D): This answer choice is an attractive wrong answer by bringing in the issue of teenage accidents at night. It is an invitation to introduce additional assumptions, specifically that the change in school start time will be insignificant because "many" teenage accidents occur at night. There are a couple issues: (1) "many" is a nebulous quantity statement that implies "some" accidents occur at night. It does not preclude or even take away from the possibility that a significant number of accidents occur in the morning and could be lessened by a later school start time. Further, (2) this information is largely irrelevant to the matter at hand; even if "most" or "almost all" accidents involving teenagers occurred in the evening, it could still be possible that a later school start time could "reduce" teenage car accidents driving to school.
Answer choice (E): This is the correct answer choice. This answer might be clearer if you apply a quick version of the Variance Test™. Imagine that there was a steep decline in the car accidents in all the areas surrounding Granville. If this had been the case, then there would have likely been another cause for the decline in teenage car accidents in Granville (assuming that the surrounding areas did not institute a policy identical to Granville's). Such information would decidedly weaken the conclusion. The information in this answer choice is a defender against this possibility and mitigates this potential weakness.
