Which backup method involves saving only the changes made since the last backup?

The choice of incremental backup is appropriate because this method focuses on capturing only the data that has changed since the last backup, whether it was a full backup or an incremental backup. This process helps to minimize the time and storage space required for backups, as only the new or altered files are saved.

When performing an incremental backup, the backup system keeps track of the changes that occur over time, ensuring that only the most recent changes are recorded. This means that if a full backup was taken initially, the first incremental backup would capture changes made since that full backup. Subsequent incremental backups would capture only the changes from the last incremental backup.

This method is particularly efficient in terms of resource usage, but it can lead to longer restore times. When restoring data, all incremental backups since the last full backup must be applied sequentially, which requires careful management of multiple backup sets.

In contrast, a full backup saves all selected data irrespective of any changes, while a differential backup saves changes made since the last full backup, leading to larger and potentially more time-consuming backup processes as more changes accumulate over time. A copy backup is similar to a full backup but does not affect the existing backup chain and is typically used for specific needs rather than routine backup processes.