1. [单选题]After connecting a PC to an available port on a switch, you find that the PC can not access any of the resources on the LAN. No other PC's connected to the switch appear to be having any issues. What is the most likely cause for this problem?
A. The router lacks a routing table entry for the new host
B. The host switch port is assigned to the incorrect VLAN
C. The host MAC address is incorrectly configured
D. A STP instance for the new host has not been initialized
E. The switch does not have the MAC address hard coded in the CAM table.
2. [单选题]The Ezonexam network administrator needs to a switch named VE1 to become the root bridge for a redundant path switched network. What can be done to ensure that VE1 will always assume the role as the root bridge?
A. Assign the switch a higher MAC address than the other switches in the network have
B. Establish a direct link from the switch to all other switches in the network
C. Configure the switch full-duplex operation and configure the other switches for half-duplex operation
D. Configure the switch so that it has lower priority than other switches in the network
E. None of the above
3. [单选题]下面哪个操作可以使访问控制列表真正生效（）。
A. 将访问控制列表应用到接口上
B. 定义扩展访问控制列表
C. 定义多条访问控制列表的组合
D. 用access-list命令配置访问控制列表
