Given the task definition and input, reply with output. In this task, you will be shown a conversation. You need to write a question with three choices for the conversation. Your question should be answerable based on the conversation and only have one correct answer. Note that you don't need to answer your question. "W" and "M" in the conversations stand for "woman" and "man".

M: Hello, Mrs. Chu. Do you feel better today? W: Oh, much better. Thank you. M: Can I ask you some questions now? W: Certainly. M: First, do you remember what the driver looks like? W: Yes. He was about fifty. He looked quite old and not very tall. Oh, and he had thick lips. M: OK. When the accident happened, where were you going? W: I was walking fast because I had to help my grandson to pay a bill. M: I see. After the driver knocked you down, he got out of his car and looked at you, didn't he? W: Yes, he did. I was bleeding, so he looked scared and then hurried back to the car. M: Do you remember his clothes? W: Yes. I looked at him when he was getting in his car. He wore an orange T-shirt, grey trousers, and leather shoes. M: Ok, I think I have enough information now. Thank you. W: You're welcome.
Who is the man? (A) A policeman. (B) A researcher. (C) A witness.