In act 2 it was the nurse
I believe the answer to this question is D. correct as is.
The type of clause that the clause or the phrase does have is in letter C. adverbial clause. Adverbial clause is a dependent clause that functions as an adverb; that is , the entire clause modifies a verb, and adjective, or another adverb. I hope you are satisfied with my answer and feel free to ask for more