单项选择题
A./etc/hosts
B./etc/resolv.conf
C./etc/netsvc.conf
D./etc/named.boot
单项选择题 WhichofthefollowingoptionsbestjustifieswhyaDNSservershouldberuninalargenetworksystem？（）
单项选择题 WhendividinganexistingClassBnetworkinto2subnetsof32，766hostseach，whichofthefollowingsubnetmasksshouldbeused？（）
单项选择题 Ahostistobecomepartofahierarchicalnamingtopology.Whichofthefollowingservicesarerequired？（）