Final answer:
File Transfer Protocol (FTP) is primarily used for transferring files between a client and server on a computer network.
Step-by-step explanation:
The primary purpose of File Transfer Protocol (FTP) is C) File transfer. FTP is a standard network protocol used for the transfer of computer files between a client and server on a computer network. It provides a way for users to download files from or upload files to a remote network, which can include web servers, FTP servers or other types of file repositories on the Internet.