Which three choices are BGP Extended communities used in MPLS-VPN deployment？（）

A.router（config）#
B.router（config-if）#
C.router（config-vrf）#
D.router（config-router）#
E.router（config-router-af）#

A.EtherChannel technology helps aggregate traffic grouping multiple，full-duplex point-to-point linkstogether
B.EtherChannel technology is based on the 802.1 IEEE stand
C.EtherChannel can aggregate up to 800 Mbps，8 Gbps，or Gbps of aggregate bandwidth for a Fast EtherChannel，Gigabit EtherChannel，or 10 Gigabit EtherChannel connection respectively
D.EtherChannel is defined for Rapid Spanning Tree for faster convergence