Given the task definition and input, reply with output. In this task, you will be shown a conversation and a question. You need to answer the question and choose the correct option based on the conversation. "W" and "M" in the conversations stand for "woman" and "man".

M: Would you please type these letters before 6, Miss Grace? F: All right, Mr. Black., Question: What is the relation between the two persons? (A) Teacher and student (B) Husband and wife (C) Manager and secretary
(C) Manager and secretary