How does encryption protect data at rest and in transit?

• A. It guarantees data never changes.
• B. It prevents all insider threats.
• C. It eliminates the need for backups.
• D. It renders data unreadable without keys and protects integrity and confidentiality during storage or transfer.

Answer: (D)

Encryption makes data unreadable without the proper keys, whether it’s stored (at rest) or moving across a network (in transit). When paired with integrity protections, it also guards against tampering, preserving both confidentiality and data integrity during storage and transfer. The other options miss the mark: encryption does not guarantee that data never changes, it doesn’t prevent all insider threats, and it doesn’t eliminate the need for backups.