If a backup session on optical media like CD and DVD is closed, it becomes read-only and can no longer be affected by a virus (so long as a virus or infected file was not copied onto the CD/DVD)
A
Correct answer
Explanation
When optical media like CDs and DVDs are closed (finalized), they become read-only and cannot be modified or written to again. This makes them immune to virus infection after finalization, provided no infected files were already on them when burned. This is a key advantage of optical media for long-term backups.