Answer:
The correct answer for the given question is "s/mime standard".
Explanation:
The s/mime standard is a secure multipurpose standard that is used for the encryption of the public key. This standard provides the security and it is used in the configuring digital signature for the setting of emails.
The main advantage of s/mime standard is to provide the linear way to send and received the data of MIME. This standard id used to protect the emails from unwanted access.