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

A.The authentication method list used by the vty port is named test.
B.If the TACACS+ AAA server is not available， no users will be able to establish a Telnet session with the router.
C.If the TACACS+ AAA server is not available， console access to the router can be authenticated using the local database.
D.The authentication method list used by the console port is named test.