You have received an invitation to a business reception with an important client marked RSVP(Please Respond), you are tentatively scheduled to leave on a business trip that day. You should …（ ）

A、ignore the RSVP because you probably can’t attend.
B、call immediately and explain the problem, asking if you can RSVP later when your schedule is firm.
C、RSVP, so you will have it covered, then don’t go if your trip comes through.
D、RSVP, then call to cancel at the last minute if your trip comes through.