Which principle ensures data is not altered without authorization?

• A. Confidentiality
• B. Integrity
• C. Availability
• D. Non-repudiation

Answer: (B)

Data integrity ensures information remains accurate and unaltered unless changes are authorized. It uses mechanisms like cryptographic hashes, digital signatures, and message authentication codes to detect tampering; if data is changed without permission, those checks will reveal the alteration and allow the system to reject or flag the data. This differs from confidentiality, which protects data from disclosure; availability, which ensures data is accessible when needed; and non-repudiation, which provides proof about the origin and delivery of a message. For example, a file protected with a hash will fail the integrity check if anyone alters it, signaling unauthorized modification.