单项选择题
What is the subnetwork number of a host with an IP address of 172.16.210.0/22?（）
A. 172.16.42.0 B. 172.16.107.0 C. 172.16.208.0 D. 172.16.252.0 E. 172.16.254.0
多项选择题 Which statements describe the routing protocol OSPF?（）
单项选择题 On point-to-point networks, OSPF hello packets are addressed to which address?（）
多项选择题 Which of the following IP addresses can be assigned to host devices?（）
