Detailed Instructions: You are given a sentence, a question and two answer options ('A' and 'B'). Your task is to find the correct answer (return the string of the correct option, not 'A' or 'B') for the given question.
Q: Sentence: A glider moves at a lower rate of speed through the treetops then through the air. Question: Which surface is smoother? (A) treetops (B) air
A:
air