Which types of backups does not set the archive bit?

Incremental backups and differential backups do not set the archive bit. Instead, they rely on the current state of the archive bit to determine which files have been changed since the last full backup. When an incremental backup is performed, it only backs up files that have changed since the last backup of any type, while a differential backup backs up all files that have changed since the last full backup, without altering the archive bit status of those files.