A Digital Signature enhances a document in which of the following ways?

• A. Verify important documents
• B. Confirm a document was reviewed
• C. Protect documents from being changed without notice
• D. Encrypt the document

Answer: (D)

Digital signatures are about proving who signed a document and ensuring it hasn’t been altered since signing. The process creates a unique signature by hashing the document and encrypting that hash with the signer’s private key. Anyone with the signer’s public key can verify the signature by decrypting it and comparing the result to a new hash of the received document. If the hashes match, you know the document is intact and that it came from the claimed signer. That tamper-detecting capability is why a digital signature protects a document from being changed without notice.

Encryption, on the other hand, hides the content of the document to keep it confidential, which is a different purpose. So while encryption secures the text, a digital signature primarily provides integrity and authenticity. That’s why the option describing protection against undetected changes is the best fit. The idea that a signature proves the document was merely reviewed or that it encrypts the document doesn’t align with how signatures function.