单项选择题

[听力原文]
M: Mary, our meeting may last longer than planned. Would you call my wife and tell her I wouldn’t have supper at home
W: Yes, sir. If anyone calls while you are out, I’ll take the message.

What do you think is the possible relationship between the man and woman()

A.Husband and wife.
B.Teacher and student.
C.Manager and secretary.
D.Doctor and patient.