Definition: You are given a sentence, a question and two answer options ('A' and 'B'). Your task is to find the correct option for the given question. Write down the answer index: 'A' or 'B'.
Input: Sentence: A model car rolling across a desk is experiencing more friction then one rolling across a display case. Question: Which surface will give the model car a rougher ride? (A) display case (B) desk
Output:
B