Question

Locate the infinitive and determine how it is used. She got up to leave.

Answer 1

The Infinitive is "to leave"
The word leave is an adverb.

I don't know if there was a "c" option but D is the answer.

Answer 2

The correct answer is D.

The infinitive in this phrase is "to leave," and it is functioning as an adverb.

Adverb infinitives are used to modify verbs. This in an adverbial modifier of purpose: "to leave" is modifying "got up," therefore, it is explainin the reason for which she has gotten up.