We apologize for any inconvenience you have been caused by the delay of the flight.
A. may
B. would
C. must
D. need
网友回答
(答案→)A. may
B. would
C. must
D. need
解析：考查情态动词，A. may+have done过去可能做了，表示不确定的推测，B. would+have done过去本来会做而没做，，C. must+have done过去一定，D. need+have done过去本有必要做却没做，句意是;我们为大家可能因为航班的延误导致的不便而道歉。选A。