To better control disk utilization, you need to use disk quotas to send an e-mail to users when they have consumed 80 MB of disk space and to prevent users from consuming more than 100 MB of disk space.
Create a single hard quota with a 100 mb limit. create a warning at 80 percent.-a. incorrect: creating a hard quota at 80 mb would prevent the user from saving more than 80 mb of files, which does not meet your requirements.b. incorrect: creating a soft quota with a 100 mb limit would not prevent users from exceeding the quota.c. correct: the most efficient way to meet your requirements is to create a single hard quota with a 100 mb limit. the hard quota prevents users from saving files ifthey exceed their quota limit. creating a warning at 80 percent would allow you to configure the quota to send an e-mail to the user when the user has consumed 80 mb of disk space.d. incorrect: soft quotas allow the user to continue to save files once the user has exceeded the quota. for this reason, it would not meet your requirements.