PrepTest 149, Section 4, Question 7
In one study, hospital patients' immune systems grew(71 more words not shown)
The argument is most vulnerable(7 more words not shown)
- Aoverlooks the possibility(23 more words not shown)
- Bfails to address(24 more words not shown)
- Cpresumes, without providing(14 more words not shown)
- Dtakes for granted(16 more words not shown)
- Epresumes, without providing(23 more words not shown)
Reading the argument
Maybe the people who usually laugh a lot also laughed a lot during this study.
There are several questions we could ask along the way. Watching comedy isn't automatically the same as laughing. A stronger immune system isn't itself a measurement of recovery. And perhaps patients were receiving medicine that also contributed to their improvement. Those are reasons to be careful about jumping straight from the videos to a claim about laughter causing recovery.
But look at the final comparison. The author says the naturally more laughter-prone patients benefit more even when they laugh less than other patients. Where did we get that comparison of amounts? The study tells us which patients had a greater tendency to laugh and which showed greater gains. It doesn't tell us that the first group actually laughed less.
What we’re looking for
Even if we grant a benefit from laughter, the amount might explain the different gains. A patient who usually laughs easily could lose that advantage when barely laughing, while someone less naturally inclined to laugh could benefit from laughing a great deal. For the flaw, I'd focus on that leap from a person's usual tendency to a benefit that supposedly exceeds what other people get from more actual laughter.
Working the answers
- ACorrect
The more laughter-prone patients might simply have laughed more at the videos. Their greater gains would then fit an explanation based on the amount of laughter, without showing that their usual disposition makes a little laughter especially powerful. A doesn't prove that amount is the cause. It points out a possibility the study must address before supporting the conclusion's comparison of little versus greater amounts.
- B
Starting stronger isn't the same as gaining more strength. Imagine one group's score rising from 80 to 90 and another's from 40 to 60. The first finishes stronger, but the second gains more. Here the evidence already compares gains, not just final strength. A higher starting point alone doesn't explain away that comparison or expose the unsupported claim about how much laughter produced it.
- C
The conclusion is about hospital patients, the group studied. It doesn't extend the result to the entire population. Hospital patients could differ from healthy people while the specific inference about these patients still faced exactly the same problem.
- D
Improvement might influence later laughter, but that doesn't establish that a preexisting tendency makes a small amount of laughter more beneficial than another patient's larger amount. The evidence specifically identifies the tendency before the gains. D's proposed later influence doesn't directly address the missing comparison of how much the groups actually laughed during the study.
- E
Getting more help with recovery doesn't have to mean recovering faster than another patient. Illnesses and starting conditions could differ. The argument doesn't require the laughter-prone group to win a race to recovery; it claims a greater benefit from even less laughter. E substitutes recovery speed for that particular comparison.
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