Logical reasoning PrepTest 133 · Section 2 · Question 1

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Weaken

Stimulus Summary:
X helps cure a disease as well as Y, and it's cheaper and faster. Therefore, X is better than Y in treating this disease.

Answer Anticipation:
This argument reaches a comparative conclusion—X is better than Y in treating a disease—based on comparative premises. When an argument reaches a comparative conclusion, it needs to establish the criteria for that comparison, as well as compare the elements along those criteria.

Here, the stimulus does compare the two elements on many criteria—effectiveness (the same), cost (X is better), speed (X is better). These criteria would suggest that X is better. But the argument never establishes that speed, cost, and effectiveness are the only or the most important criteria.

As such, any answer that brings up a relevant comparison showing Y as being better along a certain metric will weaken this argument. For instance, Y might have fewer side effects.

Answer Explanation:
This answer highlights a metric on which Y is better than X. X having harmful side effects calls into question whether it's better than Y despite similar effectiveness, lower costs, and faster speed. In bringing up a metric where Y is better than X and that might be more important than the criteria discussed in the stimulus, this answer weakens the argument.

Key Takeaway:
Comparative arguments are generally weakened by comparisons. Here, the argument concluded that X was better than Y. It was based on some differences where X was better. As such, you can expect the correct answer to bring up a comparison where Y is better.

Incorrect. The conclusion is limited to treating "these illnesses," so other illnesses are out of scope.

Incorrect. The argument is discussing the present, not the past, so this answer brings up information that's out of scope.

Incorrect. How frequently a treatment is prescribed isn't related to its efficacy or whether it's a better option, so this comparison is out of scope.

Incorrect. The conclusion is that X is better than Y, not that X is the best option, so treatments other than X and Y are out of scope.