单项选择题
A.Configure the no ip subnet-zero command on R1, R2, and R3.
B.Dynamic routing protocols such as RIPv2 cannot be used across Frame Relay networks.
C.Configure the S0/0 interface on R1 as two subinterfaces and configure point-to-point links to R2 and R3.
D.Change the 172.16.2.0/25 and 172.16.2.128/25 subnetworks so that at least two bits are borrowed from the last octet.
E.Change the network address configuration to eliminate the discontiguous 172.16.2.0/25 and 172.16.2.128/25 subnetwork.
单项选择题 为了允许建立一个TELNET会话，以下哪个命令集必须被配置？（）
单项选择题 What value is primarily used to determine which port becomes the root port on each nonroot switch in a spanning-treetopology?（）
单项选择题 A network administrator wants to add a line to an access list that will block only Telnet access by the hosts on subnet 192.168.1.128/28 to the server at 192.168.1.5.What command should be issued to accomplish this task？（）
