Which backup type would be used to restore quickly after a disaster by applying the latest differential backup to the most recent full backup?

• A. Full backup
• B. Differential backup
• C. Incremental backup
• D. Archive backup

Answer: (B)

Differential backups store every change since the last full backup, so restoring quickly after a disaster is straightforward: you restore the most recent full backup, then apply the latest differential backup. This brings the data up to date with just two pieces to restore, avoiding the longer, more fragile process of applying a chain of many incremental backups. The differential approach balances speed and currency—faster than incremental-only restores, and more up-to-date than using only a full backup.

A full backup alone would give you a complete snapshot but may not include changes that happened after that backup. An incremental backup would require applying a series of backups from the last full to reach the current state, which takes longer and increases the risk of missing a piece. An archive backup is typically for long-term retention and not designed for rapid disaster recovery of the current operational data.