Cabin altitude is normally rate-controlled by the cabin pressure controller up to a cabin altitude of ____ feet at the airplane maximum certified ceiling of ____feet.
A.A.10 000 ft and 41 000 ft.
B.B.8 000 ft and 41 000 ft.
C.C.12 000 ft and 41 000 ft.
D.D.7 500 ft and 41 000 ft.
正确答案是B