Which controls verify document integrity and detect tampering?

Which controls verify document integrity and detect tampering?

• A. Only access controls.
• B. Encryption without integrity checks.
• C. Digital signatures, hashes, watermarks, and tamper-evident controls.
• D. No controls used.

Answer: (C)

Ensuring a document hasn’t been altered and that its origin can be trusted relies on mechanisms that provide verifiable evidence of the content and any changes. A cryptographic hash creates a unique fingerprint of the document; any modification changes the hash, so you can detect tampering by comparing to the original digest. A digital signature signs that hash with a private key, and anyone with the corresponding public key can verify the signature to confirm both the document’s integrity and the signer’s authenticity. Watermarks add a visible or embedded marker that helps show if the content has been copied or altered, while tamper-evident controls physically or digitally reveal if the document has been opened or modified. Together, these tools give you reliable ways to detect changes and verify origin. Access controls protect who can view or modify a document but don’t prove that the content remained unchanged. Encryption without integrity checks protects confidentiality but not whether tampering occurred. No controls in place would leave tampering undetected.

Ensuring a document hasn’t been altered and that its origin can be trusted relies on mechanisms that provide verifiable evidence of the content and any changes. A cryptographic hash creates a unique fingerprint of the document; any modification changes the hash, so you can detect tampering by comparing to the original digest. A digital signature signs that hash with a private key, and anyone with the corresponding public key can verify the signature to confirm both the document’s integrity and the signer’s authenticity. Watermarks add a visible or embedded marker that helps show if the content has been copied or altered, while tamper-evident controls physically or digitally reveal if the document has been opened or modified. Together, these tools give you reliable ways to detect changes and verify origin.

Access controls protect who can view or modify a document but don’t prove that the content remained unchanged. Encryption without integrity checks protects confidentiality but not whether tampering occurred. No controls in place would leave tampering undetected.