Which sentence uses an infinitive phrase as an adverb? A) Whenever I feel afraid, I usually try to hum my favorite song's melody. B) My neighbor was extremely angry when our dog stirred up his dog into barking all night. C) Seth is taking scuba diving classes to prepare for his cruise to the Bahamas this summer. D) The library has just purchased every single one of the books in the Merlin Sorcery series.
Since an infinitive phrase is a phrase (does not contain a subject or verb and does not convey a complete thought) that consists of the word "to" and a verb, the answer would be C since the verb is ''prepare" and the infinitive phrase is "to prepare".
