PrepTest 134, Section 2, Question 18
Journalist: Recent studies have demonstrated that a regular(61 more words not shown)
If the journalist's statements are(10 more words not shown)
- AThe short-term memory(31 more words not shown)
- BThe short-term memory(27 more words not shown)
- CThe short-term memory(30 more words not shown)
- DA regular smoker(37 more words not shown)
- EThe short-term memory(30 more words not shown)
Reading the argument
Which people are being compared? A regular smoker who has just smoked typically performs better on short-term memory than a nonsmoker, even if the nonsmoker also smoked for the study. That is a comparison between groups, not proof that a cigarette improved either person's memory.
Maybe smoking explains the difference; maybe the groups differed already. The journalist doesn't draw a causal conclusion, so we shouldn't add one.
We get one further fact: most of the regular smokers who show this advantage keep it for at least eight hours. At least eight doesn't mean exactly eight or no more than eight.
What we’re looking for
The task is to find what cannot be true. Four choices can fit alongside these facts; one conflicts with something we were told. Keep both the people and the timing straight as we check them.
Working the answers
- A
This compares two groups of nonsmokers: those who just smoked and those who didn't. The passage compares regular smokers with each of those groups, but it never ranks the two nonsmoker groups against one another. Both could perform worse than regular smokers while one nonsmoker group also performs worse than the other. A is possible.
- BCorrect
These are the same groups and timing as the first statement, but with the ranking reversed. The passage says a regular smoker who just smoked typically does better than a nonsmoker who just smoked. B says that nonsmoker typically does better than the regular smoker. That directly conflicts with the reported comparison, so it is our exception.
- C
Here the regular smoker has gone more than eight hours without smoking. The passage guarantees no particular typical ranking at that later point. Saying that most of those with the advantage retain it for at least eight hours doesn't tell us whether it lasts beyond eight or how the later group compares with nonsmokers who just smoked. C could fit.
- D
Typically doesn't mean every regular smoker, so the individual who shows no immediate advantage can be an exception. The passage also doesn't tell us what happens after a period of heavy smoking rather than after one cigarette. That person's later improvement is therefore compatible with the reported findings. We don't have to establish that it really happens to see that no stated fact rules it out.
- E
This compares regular smokers with other regular smokers at different times since their last cigarette. We are told that an advantage over nonsmokers often persists for at least eight hours, but not that its size stays constant. Performance five hours later could be better than performance immediately afterward while both groups still outperform nonsmokers. E doesn't contradict the stated comparison.
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