单项选择题
A.mkuser
B.cruser
C.adduser
D.edit /etc/password
单项选择题 Auserwantstobepermanentlyaddedtothedbagroup.Whichcommandorprocesscanbeusedtoaccomplishthis？（）
单项选择题 Duetooperationalcommitments，asystemhasaveryshortbackupwindowduringtheweek，butisnotusedfromSaturdaymorningthroughSundayatMidnight.Whichofthefollowingminimizesbackuptime，whileprovidingthebestdatarestorecoverage？（）
单项选择题 AsystemadministratorperformsafullbackupeverySaturdayeveningandincrementalbackupstherestoftheweek.ThesystemfailedonThursdayandneedstoberestored.Whichbackuptapeswillberequiredtorestorethesystemtoitsmostrecentrecoverablestate？（）