Though the mayor's speech was widely lauded for its rhetorical flourish, critics argued that it ultimately proved ______, offering grand pronouncements without any ______ plans for implementation.

The correct answer to the question "Though the mayor's speech was widely lauded for its rhetorical flourish, critics argued that it ultimately proved ______, offering grand pronouncements without any ______ plans for implementation." is Option C: vapid, concrete.

The other options — A) substantive, comprehensive, B) consequential, actionable, D) insightful, pragmatic — are incorrect for this GRE Exam Prep question. As explained above: The speech was 'lauded for its rhetorical flourish' but critics found it '______,' offering 'grand pronouncements without any ______ plans.' 'Vapid' (lacking spirit, liveliness, or substance) fits th…