Answer:
adverb clause
Explanation:
An adverb clause is a group of words that function as an adverb in a sentence. The clause can modify or describe verbs, adverbs, and adjectives. In general, adverb clauses add information that elaborates on when, where, why, how, how much or under what condition the action in the sentence takes place.
The answer is c. Honey was used as a preservative in ancient times
