Read the following conversation and answer the question.

W: Look! Is that Tom over there, the boy reading a book?

M: That can't be Tom. That must be his brother Jim.

W: Why?

M: Because Tom flew to Beijing just last night. He couldn't have returned yet.

Question: What are the speakers mainly talking about? 

- When Jim will return.

- When Tom flew to Beijing.

- Who is reading a book there.


Who is reading a book there.