GRE Vocabulary Builder

Answer: Choice (D) is correct.

In the first half of the analogy, something that is nebulous is vague or ill-defined, not precise. So, look for the answer choice that contains antonyms. In choice (A), something that is lurid is gruesome and shocking, so eliminate that choice. In choice (B), something that is insouciant is carefree and unconcerned. In choice (C), something that is luculent is easily understood and clear. The only choice that contains antonyms is choice (D). Something that is piquant is spicy or tangy, not bland or tasteless.