Answer:
Digital Signature
Step-by-step explanation:
Digital Signatures are used in electronic messages to verify the sender's ıdentity. It is a online signature and highly secure way of proving identity.
The Signature is encrypted and can be decoded using public-key .
Digital signatures are certificated uniquely from accredited providers, encrypted and can be validated by certificate authorities.
Messages with digital signatures prove that the message sent by the owner of the signature and didn't changed on the way.