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.

Sentence: When playing pinball on two different machines, joe noticed that the pinball moved quickly over the glass surface whereas it barely moved at all over the mud surface. Question: Which surface showed less resistance? (A) Glass (B) Mud
Glass