Which of the following MUST Matt, a security administrator, implement to verify both the integrity and authenticity of a message while requiring a shared secret?

RIPEMD is a cryptographic hash function that provides integrity checking only and does not incorporate a shared secret for authentication.

MD5 is a hashing algorithm that can verify integrity but does not use a shared secret and is not designed to provide message authenticity.

SHA is a family of hash algorithms that checks integrity but, like MD5, does not use a shared secret and cannot verify the identity of the sender.

HMAC combines a cryptographic hash function with a shared secret key, producing a message authentication code that verifies both that the message has not been altered (integrity) and that it came from a party holding the shared secret (authenticity). Neither party can verify the MAC without possessing the shared secret, satisfying both requirements simultaneously.