私有C类IP地址有（）个。

A.aaa accounting network start-stop tacacs+
B.aaa accounting system start-stop tacacs+
C.aaa accounting exec start-stop tacacs+
D.aaa accounting connection start-stop tacacs+

A.直连路由
B.静态路由
C.动态路由
D.默认路由

A.Router（config）#password-encryption
B.Router（config）#service password-encryption
C.Router#service password-encryption
D.Router#password-encryption