单项选择题

Questions 4 to 6 are based on the following conversation. At the end of the conversation, you will be given 15 seconds to answer the questions. Now, listen to the conversation.
What does the woman offer to do

A.Teach Don’s class while he is absent.
B.Give the man the key to Don’s office.
C.Make an appointment with the doctor.
D.Return some exams to the students.