Which of the following ports should be used by a system administrator to securely manage a remote server?

SSH (Secure Shell) operates on TCP port 22 and provides encrypted authentication and command execution for secure remote server management. It replaced insecure protocols like Telnet (port 23) and rsh, ensuring that credentials and session data are protected from interception in transit.

Port 69 is used by TFTP (Trivial File Transfer Protocol), an insecure and unauthenticated file transfer protocol that is not suitable for remote management.

Port 137 is used by NetBIOS Name Service for Windows name resolution and has no role in secure remote server administration.

Port 445 is used by SMB (Server Message Block) for Windows file and printer sharing and is not used for remote command-line management.