单项选择题
A、Quidway（config-if-s0）#backup state-down10
B、Quidway（config-logic-channel8）#backup state-down10
C、Quidway（config-logic-channel8）#backup delay1010
D、Quidway（config-int-s0）#backup delay1010
E、Quidway（config-int-s0）#backup state-down1010