单项选择题 A server has five hot pluggable SCSI disk drives in a RAID 5 array. The server OS crashed and the server will not boot. The administrator noticed that all of the disk drives have gone offline.Which of the following components would MOST likely have caused the problem?（）

多项选择题 WhenconfiguringaDHCPserver，whichofthefollowingcantheadministratordefineforDHCPusers？（）

单项选择题 Which of the following is the LEAST intrusive?（）