答案：C
试题一 [说明] 某局域网的IP地址为61.100.13.0/24，采用DHCP服务器(DHCPServer)自动分配IP地址，网络结构如图5.73所示。 PCI首次启动时，DHCP工作流程为：寻找DHCP服务器、提供IP租用、接受IP租约及租约确认等4步，如图5.74所示。
为图5.74中(1)～(4)处选择正确的报文。
A．Dhcpdiscover
B．Dhcpoffer
C．Dhcprequest
D．Dhcpack
There are two main sets of Games — the Winter and the Summer Olympics, and both are held every four years on a _________ basis.
A．valuable
B．former
C．regular
D．swift
