Answer: Integrity verification of message.
Explanation: Digital signature is used for the security purpose of the documents by the encryption technique such as passwords etc.The signature is created electronically for a digital document protection.The document is authenticated if correctly signed by the user/signer .
The collection of algorithms that are encrypted verifies the authenticity while being transferred if document content does not get tampered.This is the verification of integrity of the message sent from the sender to the signer.