单项选择题

A.cv2.morphologyEx(image,cv2.MORPH_OPEN,e)
B.cv2.morphologyEx(image,cv2.MORPH_CLOSE,e)
C.cv2.morphologyEx(image,cv2.MORPH_GRADIENT,e)
D.cv2.morphologyEx(image,cv2.MORPH_TOPHAT,e)