PrepTest 139, Section 1, Question 24
In an effort to reduce underage drinking, the(59 more words not shown)
The reasoning in the argument(8 more words not shown)
- Abases a conclusion(21 more words not shown)
- Bfails to consider(12 more words not shown)
- Cinfers from an(20 more words not shown)
- Dtreats a condition(17 more words not shown)
- Econfuses the claim(26 more words not shown)
Reading the argument
Would these teenagers have avoided alcohol anyway?
Taking a pledge isn't automatically what changes someone's behavior. Imagine a teenager whose family expectations and personal beliefs already rule out drinking. That teenager might readily sign the pledge and continue not drinking. Someone already planning to drink might decline to sign. We'd see the reported association even if signing changed neither teenager's decision.
What we’re looking for
The survey therefore gives us something worth investigating, but it doesn't isolate the pledge's effect. To call the program successful, the author needs more than a connection between taking the pledge and abstaining. The flaw is treating that connection as evidence that the pledge caused the abstention, without accounting for the possibility that people who choose the pledge already differ from those who don't.
Working the answers
- A
The author points to survey results, not a moral judgment that underage drinking is wrong. Whatever motivates the department's program, the stated evidence for its effectiveness is the association between pledging and not drinking. A misdescribes that evidence.
- B
Another method could be more effective while this one still helped. The conclusion says the pledge seems successful, not that it's the best possible way to reduce underage drinking. Comparing it with every alternative wouldn't resolve whether this observed association reflects a real effect of the pledge.
- CCorrect
The author moves from finding an association to crediting the pledge with causing people not to drink. But the people willing to take the pledge might already be committed to avoiding alcohol. In that case, the pledge would identify an existing difference rather than produce the change the department wants.
- D
The argument doesn't establish that taking the pledge guarantees abstention and then treat pledging as the only way to abstain. It uses an observed association to support a causal claim. The error is about what explains the pattern, not about exchanging a requirement with a guarantee.
- E
The same people can be described from either side of this overlap. Adolescents who both abstain and report taking the pledge are also pledge-takers who abstain. Restating that overlap doesn't create the causal mistake. The unsupported step is deciding that the pledge made them refrain from drinking.
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