Which of the following protocols pushes email messages to the server? A. HTTP B. Both, POP and HTTP C. POP D. SMTP

The correct answer is: D. SMTP

SMTP (Simple Mail Transfer Protocol) is a standard protocol for electronic mail (email) transmission. SMTP is an application-layer protocol that is typically used to send email messages from an email client to an email server, or from one email server to another.

POP (Post Office Protocol) is a standard protocol for accessing email from a remote server. POP is typically used to download email messages from an email server to a local computer, where they can then be read and managed using an email client.

HTTP (Hypertext Transfer Protocol) is a standard protocol for accessing and transferring hypertext documents

However, HTTP is not a reliable protocol for sending email messages, as it is not guaranteed that the message will be delivered. SMTP is a more reliable protocol for sending email messages, as it provides a mechanism for confirming that the message has been delivered.

Therefore, the correct answer is: D. SMTP