GRE Vocabulary Builder

Answer: Choice(C) is correct.

Ostensible means apparent or perceived, not inconspicuous, or unnoticeable. So, look for the answer pair that contains antonyms. In choice (A), assiduous means diligent and hard-working, as does sedulous. These are synonyms, so eliminate choice (A). In choice (B), chary means cautious or wary, so eliminate that choice. In choice (D), austere means serious or somber. Something that is austere is definitely not adorned with anything, so eliminate that choice. In choice (C), to be cognizant is to be aware or mindful, not unaware.