The correct option is A Prolix
'Prolix' is synonymous with wordy and, therefore, matches the meaning conveyed in this sentence. This is clear since it is mentioned that the author uses circumlocutions, which means 'a style that involves indirect, and usually lengthy, ways of expressing things'. 'Monotonous' means boring and 'vapid' means dull/ tasteless. 'Risque' means suggestive or indecent.