单项选择题
A.mpls ip cef
B.port-channel ip cef
C.mpls ip port-channel cef
D.port-channel load balance
E.mpls ip load-balance
F.ip cef EtherChannel channel-id XOR L4
G.ip cef connection exchange
单项选择题 Refer to the exhibit. In the diagram， the switches are running IEEE 802.1s MST. Which ports are in the MST blocking state？（）
单项选择题 WhichstatementistrueaboutTCNpropagation？（）
单项选择题 Refer to the exhibit. Catalyst R is the root bridge for both VLAN 1 and VLAN 2.What is the easiest way to load-share traffic across both trunks and maintain redundancy in case a link fails，without using any type of EtherChannel link-bundling？（）