阅读下面的短文，掌握其大意，然后从短文后各题所给的选项中，选择最佳选项。

Steve is a middle school student. His school is not far 1 his home. He usually comes home after the school 2 at five. But today Steve 3 doesn't come back at half pas six. When he 4 at home at seven, Mom asks him, "5 are you late today, Steve?" "My teacher asks you to go to our 6 tomorrow. He wants to have a 7  with you," says Steve.

"To your school? Why? Because he asks us a question, and only I 8 the answer (答案)," Steve says. "Really? You are 9," Mom is very happy. "What is his question?" "His question is 'who spilt (洒) the milk on my chair? It makes my trousers 10. '