Which type of backup includes a copy taken from every file on the system?

A full backup is indeed the choice that represents a copy taken from every file on the system. The primary purpose of a full backup is to create a complete and comprehensive copy of all data, files, and system settings at a specific point in time. This means that after completing a full backup, there is a single snapshot of the entire dataset, which makes it easier to restore the system to that exact state if needed.

In contrast, incremental backups only capture the changes made since the last backup—either the last incremental or a full backup—thus not including every file each time. Mirrored backups create an exact copy of the data, but they often do not retain previous versions or deleted files, which contrasts with the complete retention provided by a full backup. Continuous backups regularly update changes to files but do not create a snapshot of all files at once like a full backup does. Therefore, the essence of a full backup lies in its exhaustive nature, capturing the entire system's files in one go.