Which command is used to configure the external, confederation-wide AS number?

A.
Certkiller 3(config)#router bgp {as-number}

B.
Certkiller 3(config-router)#bgp confederation peers {as-number}

C.
Certkiller 3(config-router)#bgp confederation identifier{as-number}

D.
Certkiller 3(config-router)#bgp cluster-id{as-number}

E.
Certkiller 3(config-router)#neighbor {ip address} remote-as {as-number}