Read the excerpt from Pride and Prejudice by Jane Austen.

You are mistaken, Mr. Darcy, if you suppose that the mode of your declaration affected me in any other way, than as it spared me the concern which I might have felt in refusing you, had you behaved in a more gentleman-like manner.

Which type of phrase is the underlined portion of the sentence?
A.
adverbial phrase
B.
verb phrase
C.
absolute phrase
D.
adjectival phrase