| Explanation & Hint:
Among the options provided, the three that are SMTP (Simple Mail Transfer Protocol) commands are:
- HELO: This command is used to initiate a conversation with the mail server. The client sends this command to the SMTP server to identify itself and initiate the SMTP conversation.
- QUIT: This command is used to terminate the SMTP session. It informs the server that the client is done with the conversation and that the server can close the connection.
- DATA: This command is used to start the transfer of the email message body. After sending this command, the client begins sending the message content, ending with a specific sequence to indicate the end of the message.
“SEND” and “SAVE” are not standard SMTP commands used in the SMTP protocol for email transmission. |