Which of the following is a secure method of transferring a file?

What kind of question is this? No parameters?

RCP (UNIX) – stands for the Unix ‘remote copy’ command. It is a command on the Unix operating systems that is used to remotely copy—to copy one or more files from one computer system to another. It typically uses the TCP/IP protocol and the .rhosts file for authentication, but has been implemented to alternatively support Kerberos.

As described in the rlogin article, rcp is not secure for network use, because it sends unencrypted information over the network, among other things. It has largely been replaced by the ssh-based utility scp.

FTP – For secure transmission that hides (encrypts) the username and password, and encrypts the content, FTP is often secured with SSL/TLS (“FTPS”). SSH File Transfer Protocol (“SFTP”) is sometimes also used instead.

SSH – is a cryptographic network protocol for secure data communication, remote shell services or command execution and other secure network services between two networked computers that it connects via a secure channel over an insecure network:

SCP – is a means of securely transferring computer files between a local host and a remote host or between two remote hosts. It is based on the Secure Shell (SSH) protocol.

Here’s a bit of help – but the question is terrible.