单项选择题

A.队列满时:(REAR+1)%n ==FRONT,队列空时:REAR ==FRONT
B.队列满时:(REAR+1)%n ==FRONT,队列空时:(FRONT+1)%n ==REAR
C.队列满时:REAR ==FRONT,队列空时:(REAR+1)%n ==FRONT
D.队列满时:(FRONT+1)%n ==REAR,队列空时:REAR ==FRONT