Detailed Instructions: You are given a sentence, a question and two answer options. Your task is to write down the index ('A' or 'B') of the **incorrect** option for the given question.
Q: Sentence: A brown mouse and a black mouse each run through 50 foot tunnels as quickly as they can. The black mouse made it to the other end in a shorter amount of time than the brown mouse. Question: Which mouse couldn't run as fast? (A) the brown mouse (B) the black mouse
A:
B