Editorial: Teenagers tend to wake up around 8:00 A.M., the time

Question

Editorial: Teenagers tend to wake up around 8:00 A.M., the time when they stop releasing melatonin, and are sleepy if made to wake up earlier. Since sleepiness can impair driving ability, car accidents involving teenagers driving to school could be reduced if the school day began later than 8:00 A.M. Indeed, when the schedule for Granville's high school was changed so that school began at 8:30 A.M. rather than earlier, the overall number of car accidents involving teenage drivers in Granville declined. 
Which one of the following, if true, provides the most support for the argument in the editorial?

(A) Teenagers start releasing melatonin later at night and stop releasing it later in the morning than do young children.

(B) Sleepy teenagers are tardy for school more frequently than teenagers who are well rested when the school day begins.

(C) Teenagers who work at jobs during the day spend more time driving than do teenagers who attend high school during the day.

(D) Many of the car accidents involving teenage drivers in Granville occurred in the evening rather than in the morning.

(E) Car accidents involving teenage drivers rose in the region surrounding Granville during the time they declined in Granville

Source: LSAT

abhimahna · Accepted Answer

Conclusion : Changing the timings led to decline in the number of accidents.

Causal Passage.

Pre thinking Assumption: There was no other reason for the decline.

We need to strengthen it.

(A) Teenagers start releasing melatonin later at night and stop releasing it later in the morning than do young children.  --> No relation shown.

(B) Sleepy teenagers are tardy for school more frequently than teenagers who are well rested when the school day begins.  --> A TRAP but no relation ship given with the conclusion.

(C) Teenagers who work at jobs during the day spend more time driving than do teenagers who attend high school during the day.  --> We are concerned with school going children

(D) Many of the car accidents involving teenage drivers in Granville occurred in the evening rather than in the morning.  --> Same as A

(E) Car accidents involving teenage drivers rose in the region surrounding Granville during the time they declined in Granville.  --> Ok. It means there was no other reason for the decline. Since this school changed the time, we have the decline.

masakiyada · Answer

I just wanted to share my train of thought to arrive at E… 
I must admit. I got lucky on this one.

I looked for ways to strengthen the stem; sleepy teenagers can now drive to school a little later, resulting in fewer accidents…

I went through the answer choices. I couldn’t think of any scenarios to strengthen the stem until I got to E.

E made me pause, mainly because it seemed strange. I smelt some hidden twist, but I could not immediately tell what it was. I looked up and blinked a few times. Then, suddenly, a scenario popped in my head.

Sleepy teenagers can go to school little later now, so they are not as sleepy any more when they drive to school because now, all high schools in Granville start at 8:30.

One evening, a group of teenagers living in Granville goes out and has a blast. They come home a bit later than usual, saying “well, our school starts at 8:30 now, so no worries!” Then, one of the boys says “well, I go to school outside Granville.” Ones who go to high school in Granville can now sleep in a bit and still drive to school without feeling sleepy, but a poor one who goes to school outside Granville now drives to school, feeling even sleepier than usual because he came home a bit later than usual last night. He is now more prone to accidents.

ironman_97 · Answer

Complete Question Explanation 
 https://forum.powerscore.com/viewtopic.php?t=13094 
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.

VerbalBot · Answer

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Editorial: Teenagers tend to wake up around 8:00 A.M., the time

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Editorial: Teenagers tend to wake up around 8:00 A.M., the time

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