Six people were traveling in a compartment (车厢) on a train. Five of them were quiet and well behaved (举止端庄), but the sixth was a rude young man who was making a lot of trouble to the other passengers. Then the young man came back because ______.
A. he got off at the wrong station
B. he found he had left his bags on the train
C. he thought he had left something on the train

At last this young man reached his station and got off with his two heavy bags. None of the other passengers helped him, but one of men waited until the rude young man was very far away, and then opened the window and shouted to him, "You left something behind in the compartment." Then he closed the window again.
The young man turned around and hurried back with his two bags. He was very tired when he arrived, but he shouted through the window, "What did I leave behind"As the train began to move again, the passenger who had called him back opened the window and said, "A very bad impression (印象)!\