An argument states: 'Our city experienced a 15% increase in library book checkouts this year after we introduced a new late fee policy. Clearly, the new late fee policy encouraged more people to use the library.' This argument most likely commits which logical fallacy?

The correct answer to the question "An argument states: 'Our city experienced a 15% increase in library book checkouts this year after we introduced a new late fee policy. Clearly, the new late fee policy encouraged more people to use the library.' This argument most likely commits which logical fallacy?" is Option D: Post hoc ergo propter hoc (assuming causation from correlation)..

The other options — A) Ad hominem., B) Slippery slope., C) False analogy. — are incorrect for this GMAT Exam Prep question. As explained above: The argument observes two events occurring sequentially (new policy, then increased checkouts) and incorrectly concludes that the first caused the second, without considering other potential factors.