Which of the following is the greatest threat posed by backups?
A.
A backup is the source of Malware or illicit information.
B.
A backup is unavailable during disaster recovery.
C.
A backup is incomplete because no verification was performed.
D.
An un-encrypted backup can be misplaced or stolen.
Explanation:
If the data written on the backup media is properly encrypted, it will be useless for anyone without the key.
http://resources.infosecinstitute.com/backup-media-encryption/