What characteristic defines an incremental backup as opposed to a differential backup?

• A. It only saves changes made since the last incremental backup
• B. It saves all recent changes since the last full backup
• C. It requires less storage than differential backups
• D. It ensures quicker recovery of data

Answer: (A)

An incremental backup is characterized by its approach to data retention. Specifically, it only saves the changes that have occurred since the last incremental backup was performed. This means that if multiple incremental backups are made consecutively, each one will only capture the changes made after the immediate prior incremental backup. This method is efficient in terms of storage space because it only retains the most recent changes rather than accumulating all changes since the last full backup.

In contrast, a differential backup captures all changes made since the last full backup, regardless of the number of differential backups executed. This results in larger backup sizes over time, as each differential backup includes all alterations since the last full backup, accumulating more data with each session.

While it is generally true that incremental backups require less storage compared to differential backups and can speed up backup processes, these aspects are not the defining characteristics of what distinguishes an incremental backup from a differential backup. Thus, the essence of an incremental backup lies in its focus on capturing changes since the last such backup, making answer choice A the defining characteristic.