根据对话内容, 选择正确答案。

(Jack is on the phone.)

Alice: Hello!

Jack: Good morning, Mary!

Alice: I'm sorry. There is no Mary here.

Jack: Is it 472-8351?

Alice: No, it isn't. It's 472-8315.

Jack: I'm sorry. I called (拨打) the wrong number.

Alice: That's OK. Bye.

(Jack calls the right number.)

Jack: Hello! This is Jack.

Mary: Hi, Jack! This is Mary.

Jack: Mary, do you know (知道) Ms. Green's telephone number?

Mary: Ms. Green, our English teacher?

Jack: Yes. Do you know her phone number?

Mary: Yes. It's 693-5273.

Jack: Thanks, Mary.

Mary: You're welcome.