指定同/异步串口1和2的备份优先级分别为10和20的配置为()

A.backup interface 1 10; backup interface 2 20

B.backup interface serial 1 10; backup interface serial 2 20

C.backup interface 1 priority 10; backup interface 2 priority 20

D.backup interface serial 1 priority 10; backup interface serial 2 priority 20