1. [单选题]IP地址为：192.168.50.70，掩码为：255.255.255.248，则该IP地址所在子网的广播地址为（）
A. 192.168.50.32
B. 192.168.80.64
C. 192.168.50.96
D. 192.168.50.71
2. [单选题]当拓扑信息完成交换，相邻路由器具有相同的LSDB时，下列哪项OSPF邻居状态是希望得到的()
A. 2-WAY
B. FULL
C. Exchange
D. Loading
3. [单选题]An administrator issues the show ip interface s0/0 command and the output displays that interface Serial0/0 is up, line protocol is up.What does "line protocol is up" specifically indicate about the interface?
A. The cable is attached properly.
B. CDP has discovered the connected device.
C. Keepalives are being received on the interface.
D. A carrier detect signal has been received from the connected device.
E. IP is correctly configured on the interface.
