What does S/MIME stand for?

S/MIME stands for Secure/Multipurpose Internet Mail Extensions. This is a standard that allows users to send encrypted and digitally signed messages over the Internet. Its primary purpose is to enhance the security of email messages by providing a mechanism for encryption and authentication. This helps ensure that the content of the email remains confidential and verifies the identity of the sender, which is crucial for maintaining data integrity and trust in electronic communications.

The term "Multipurpose" in the name indicates that S/MIME can handle not just emails but various types of data formats, including attachments. This flexibility makes it a widely recognized and adopted protocol in secure email communications. The usage of cryptography in S/MIME allows for both symmetric and asymmetric encryption methods, making it versatile and robust in securing communication.

The other options do not accurately represent the standard's full name or its intended purpose in the context of secure email communication.