Which of the following backup methods should be used nightly to ensure backups capture all necessary data in the LEAST amount of time?

A Daily backup copies files modified on the current day using the Daily attribute, but this method is less precise than incremental and is not the standard choice for minimizing backup time in enterprise environments.

An incremental backup copies only the files that have changed since the last backup operation, whether that was a full or another incremental backup. Because the backup window is limited to just the newest changes each night, the backup set is smallest and completes fastest among the listed options. This makes it ideal for nightly runs where minimizing backup time is the priority.

A Normal (full) backup copies all selected files and clears the archive bit; it is the most time-consuming method because it backs up everything regardless of whether files changed.

A Differential backup copies all files changed since the last full backup, so its size and duration grow each night until the next full backup, making it slower than incremental over time.