Which of the following is required to be backed up on a domain controller to recover Active Directory?

The system state backup on a Windows domain controller includes the Active Directory database (NTDS.DIT), the SYSVOL share, the registry, boot files, and the COM+ class registration database. Restoring system state is the supported method for performing authoritative or non-authoritative restores of Active Directory Domain Services, as defined by Microsoft's AD DS backup and recovery guidance.

Backing up operating system files alone does not capture the Active Directory database or SYSVOL, so AD cannot be recovered from this backup alone.

Users' personal data such as documents and profiles is stored in user profile directories and has no bearing on recovering the Active Directory directory service itself.

Third-party application folders contain application binaries and data but are entirely unrelated to the Active Directory database and its recovery.