A. They can only be separate chemically
Cryptography, like digital signatures, is used to accomplish nonrepudiation, which also includes services for authentication, auditing, and logging.
Digital signatures in online transactions make assurance that a party cannot later dispute the sending of information or the validity of its signature. Alice can encrypt the communication using her own Private Key. As a result, only her public key, which she is aware Bob (and everyone else) has access to, may be used to decrypt her message. Bob receives the message, and he uses Alice's public key to decrypt it. Secret key cryptography (symmetric encryption): To encrypt and decrypt given messages, both the sender and the receiver must use the same key.
Learn more about information here-
brainly.com/question/15709585
#SPJ4
