Which property is provided by digital signatures?

• A. Availability
• B. Confidentiality
• C. Authentication and Integrity
• D. Performance

Answer: (C)

Digital signatures provide authenticity and data integrity. Signing with a private key creates a signature on a hash of the message, and anyone with the public key can verify that the signature was created by the claimed signer and that the message hasn’t been altered since it was signed. This establishes who sent the message (authentication) and ensures the content remains unchanged (integrity). They don’t inherently protect content from being read (confidentiality)—that requires encryption. They also don’t guarantee availability (being accessible) or improve performance; those aspects are outside what a signature is designed to provide.