Logical reasoning PrepTest 149 · Section 4 · Question 25

Incorrect. This answer choice treats two options as mutually exclusive, where it selects one to rule out another, instead of ruling out one to select the other. That's, in a way, the opposite of what the stimulus does.

Incorrect. This answer choice commits an illegal negation. Even if you couldn't spot that just by reading it, you still should have noted that it didn't have a list, so it couldn't fail to establish that list as comprehensive, thus missing a key element of the flaw.

Incorrect. This answer weighs alternatives and establishes that one is worse than the other, so the company should go with the less-worse alternative. Not only is that not parallel to the flaw in the stimulus, it's not flawed.

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Flawed Parallel Reasoning

Stimulus Summary:
There are two suspects: Schaeffer and Forster. It can't be Schaeffer, so it must be Forster.

Answer Anticipation:
The argument tries to proceed to its conclusion by ruling out alternatives. It does rule out all known alternatives in establishing that Schaeffer's alibi is "ironclad," but it never establishes that the list of suspects is a complete list of anyone who could have committed the crime. In failing to establish that the given list is comprehensive, this argument is flawed, so the correct answer should similarly rule out alternatives from a list that may not be complete.

Answer Explanation:
This argument establishes two options under consideration, rules one out, and concludes the other option will happen. It also fails to establish that Evansville and Rivertown are the only options under consideration. This argument follows the same format and has the same flaw, so it's the correct answer.

Key Takeaway:
When an argument proceeds by ruling out alternatives, it has to first establish that the list it's eliminated from is comprehensive.

Incorrect. This answer establishes that Slater and Gonzales are the "only viable candidates," thus establishing that the list of potential winners is comprehensive. Before you note that there could be other candidates, that's right—but they're not viable. And if they're not viable, by definition they can't win. (Note that if it said that there are only two candidates considered viable by the political analysts, then we'd be back to it not being a comprehensive list.) Even if you overlooked that mismatch with the stimulus, you still should have eliminated this answer because it starts talking about the "little chance" of one option and it being "likely" that the other option will happen, which is a change from the stimulus.