Which backup method listed below will probably require the backup
operator to use the most number of tapes for a complete system
restoration, if a different tape is used every night in a five-day rotation?

A.
Incremental Backup Method

B.
Ad Hoc Backup Method

C.
Full Backup Method

D.
Differential Backup Method

Explanation:
Most backup methods use the Archive file attribute to determine
whether the file should be backed up or not. The backup software
determines which files need to be backed up by checking to see if
the Archive file attribute has been set, and then resets the Archive bit
value to null after the backup procedure. The Incremental Backup
Method backs up only files that have been created or modified since
the last backup was made, because the Archive file attribute is reset.
This can result in the backup operator needing several tapes to do a
complete restoration, as every tape with changed files as well as the
last full backup tape will need to be restored.
* a Full or Complete backup backs up all files in all directories
stored on the server regardless of when the last backup was
made and whether the files have already been backed up. The
Archive file attribute is changed to mark that the files have been
backed up, and the tapes or tapes will have all data and applications
on it. It’s an incorrect answer for this question, however, as it’s
assumed answers Differential Backup Method and Incremental Backup Method will additionally
require differential or incremental tapes.
* the Differential Backup Method, backs up only files that
have been created or modified since the last backup was made, like an
incremental backup. However, the difference between an incremental
backup and a differential backup is that the Archive file attribute is not
reset after the differential backup is completed, therefore the changed
file is backed up every time the differential backup is run. The backup
set grows in size until the next full backup as these files continue to be
backed up during each subsequent differential backup, until the next
complete backup occurs. The advantage of this backup method is that
the backup operator should only need the full backup and the one differential
backup to restore the system.
Table shows these three backup methods.
Exhibit:

Answer “Ad Hoc Backup Method” is a distracter.