Digital signatures provide which assurance?

• A. Non-repudiation
• B. Confidentiality
• C. Data integrity
• D. Availability

Answer: (A)

Digital signatures create a verifiable link between the signer and the exact content by signing a hash of the data with the signer's private key. Anyone with the signer’s public key can confirm who signed it and that the data hasn’t been altered since signing. This binding makes it possible to prove authorship and prevents the signer from later denying having signed the message—non-repudiation. While signatures also protect against tampering (data integrity), they do not hide the content (confidentiality) and do not address system availability.