PrepTest 107, Section 3, Question 23
Several carefully conducted studies showed that 75 percent(43 more words not shown)
The flawed pattern of reasoning(17 more words not shown)
- AThe majority of(38 more words not shown)
- BStudies have shown(41 more words not shown)
- CThe majority of(38 more words not shown)
- DStudies show that(31 more words not shown)
- EMost people who(35 more words not shown)
Reading the argument
What about people who eat meat?
Seventy-five percent of vegetarians reaching 50 without serious heart disease might sound reassuring. Or we might be concerned that a quarter developed it. Neither reaction tells us whether avoiding meat improves anyone's chances. We need something to compare that number with.
Suppose 75 percent of meat eaters also reach 50 without serious heart disease. Then the reported vegetarian result shows no advantage at all. If only 50 percent of meat eaters avoid it, the comparison would look more favorable to vegetarians. The passage supplies neither figure. Those possibilities show why the missing comparison matters.
Yet the author moves from a result for vegetarians to a claim that avoiding meat reduces risk, then recommends avoiding meat to people who want that benefit. The recommendation rests on an improvement we have not established.
What we’re looking for
For the parallel flaw, look for that same gap: an outcome in one group, an unsupported claim that its behavior improves the outcome, and advice to adopt that behavior. A choice about heart disease can sound familiar while supplying the very comparison this argument leaves out.
Working the answers
- A
We get an accident rate for speeders without a rate for other drivers, so the opening has some resemblance. But the conclusion shifts to hiring police to protect other people. It does not first claim that avoiding speeding improves a person's chances and then advise people who want that improvement to stop speeding. To match more closely, it would need that unsupported personal comparison and recommendation.
- B
This explicitly says smokers have a greater chance of heart disease than nonsmokers. That is the comparison missing from the original. B then makes a causal claim and recommends a behavior, but matching those later steps cannot make up for missing the central flaw. We need an argument that lacks the comparison, not one that already gives it.
- C
The missing information is promising: perhaps people who do not drink coffee get dental problems just as often. But C moves from its stated correlation to a government policy making coffee less accessible. The original instead claims that a behavior improves one's chances and recommends it to people who want that benefit. C does not reproduce that full route as closely as E.
- D
Again, there is an explicit comparison. Nonexercisers have shorter life expectancies than exercisers. Whatever further questions we might ask about cause and effect, this argument does not try to establish a comparative benefit using information about only one group.
- ECorrect
Regular exercisers correspond to vegetarians, and handling stress corresponds to avoiding serious heart disease. We know the favorable outcome occurs for most members of that group. We do not know how often it occurs among people who do not exercise.
Maybe most nonexercisers handle stress too. Without that comparison, E has not shown that exercise decreases the chance of being overwhelmed. It nevertheless claims that benefit and recommends exercise to people who want it. Those are the same unsupported improvement and resulting recommendation as in the original.
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