阅读理解B
Policeman(男警察): Hello!
Marcus: Hello! I lost my bag(包)this morning．
Policeman: What color is your bag?
Marcus: It's black．
Policeman: We have two bags here．Is this your bag?
Marcus: No, it isn't.
Policeman: Is that your bag?
Marcus: Yes! That's my bag!
Policeman: What's in your bag?
Marcus: My keys, my book, my green pen ... Oh, and my white phone.
Policeman: What's your name?
Marcus: Mr. Smith.
Policeman: What's your first name，Mr. Smith?
Marcus: Marcus．
Policeman: Yes，it's your bag．Here you are．
Marcus: Thank you．
根据材料内容选择最佳答案。
