Given the task definition and input, reply with output. In this task, you will be shown a conversation and a question. You need to answer the question and choose the correct option based on the conversation. "W" and "M" in the conversations stand for "woman" and "man".

W: Come to the movies with us. Everybody needs to take a break every once in a while. M: I guess I might as well. I've been studying so long I just can't concentrate., Question: Why can't the man concentrate on his study? (A) He keeps thinking of going to the movies. (B) His classmates are taking a break. (C) He's been studying for too long.
(C) He's been studying for too long.