单项选择题
A.The VLAN is misconfigured
B.The user has an improperly configured NIC
C.The DHCP server is down
D.The DNS server is down
单项选择题 Users report that they are unable to connect to a server. An administrator confirms that it is unreachable across the network. Other administrators have been working in the server room throughout the day. Which of the following is the NEXT step the administrator should take？（）
单项选择题 Auserreportsthattheyareunabletoprinttoaremoteprinter.Whichofthefollowingshouldthe techniciancheckFIRST？（）
单项选择题 WhichofthefollowingbackupmediawouldbeMOSTappropriateforrouterconfigurationfiles？（）