根据短文内容, 选择正确的答案。

Mr Smith lives in a village, but he works in a big city. He goes to work by train every morning and comes back home in the same way.

This morning, Mr Smith is reading his newspaper（报纸） on the train, a man behind him says to him, "Your life is not interesting, isn't it?You take the same train every morning, and you always sit in the same seat （座位） and read the same newspaper . " "How do you know all that about me?"Mr Smith says angrily（生气地）. " Because I always sit in the same seat behind you. "the man answers.