单项选择题

Doctor: It's the flu. Drink plenty of water and have a good rest.Patient: Do I have to stay in bed I have piles of work to do at office.Doctor: ______

A.Did you hear what I just said
B.You needn't go to the office.
C.It's OK if you have to work overtime.
D.I'm afraid you have to keep it off your mind for a week or so.