Official Explanation
D
The key to this question is the contrast between the “elated,” or excited, crowd, and the “skeptical,” or doubting, cynics. We are looking for a word that would cause the crowd to be excited, but would cast doubt among skeptics. We can immediately eliminate choice (A) stolid, “unemotional,” choice (B) verbose, “talkative,” and choice (E) diffident, “lacking self-confidence,” as these are all negative adjectives for a political speech and would not invoke the excitement of the crowd. Choice (C) whimsical, “fanciful,” seems plausible: the crowd might like a fanciful, idealistic promise, while cynics would remain doubtful of its veracity. However, choice (D) extravagant is a better choice, as it implies an attractive promise that might not be realistic.