Flawed ReasoningDiff: Medium

Logic Breakdown

Passage Summary: A company claims their soda is the best because it beat five other sodas in separate one-on-one taste tests.

Conclusion: Sparkle Cola generates a more positive consumer response than any of the five competing colas it was tested against.

Reasoning: In a study where five groups each compared Sparkle to one other cola, Sparkle was preferred by the majority in every head-to-head matchup.

Analysis: The flaw here is a mathematical and logical oversight regarding preferences. Winning a series of one-on-one matches doesn't mean you are the overall favorite of the group. For example, Sparkle could be everyone's second choice, while each 'loser' is the absolute favorite for a large minority. The argument fails to consider that 'most preferred' in a head-to-head doesn't translate to 'most preferred' in a ranked list of all six options. Look for an answer that highlights this failure to establish an absolute preference over the field.

Passage Stimulus

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15.

The reasoning in the advertisement is most vulnerable to criticism on which one of the following grounds?

Correct Answer
A
A identifies the core flaw: inferring that what’s true of the entire sample (most volunteers overall preferred Sparkle) must be true within each of the five subgroups (each competitor’s head-to-head). That leap is unwarranted and directly undercuts the conclusion that Sparkle elicits a more favorable response than any competitor tested.
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