单项选择题 Whenloadbalancingtrafficbetweentwowebservers，whichofthefollowingtechnologiesprovides theLOWESTcostsolution？（）

单项选择题 A server failed Thursday evening before the nightly backup. The backup scheme in place was fullbackups  every Sunday，incremental backups on Monday，Wednesday，and Friday，and differentialbackups on Tuesday，Thursday，and Saturday.  To fully restore the server，which of the following is theLEAST amount of backup sets required？（）

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？（）