Which of the following is the primary TCP/IP protocol used to transfer text and binary files over the Internet?

PPTP (Point-to-Point Tunneling Protocol) is a VPN tunneling protocol used to create encrypted network connections, not to transfer files.

SNMP (Simple Network Management Protocol) is used for monitoring and managing network infrastructure devices such as routers and switches, not for file transfers.

FTP operates on TCP ports 20 (data) and 21 (control) and was purpose-built for file transfers, supporting both ASCII text mode and binary mode transfers. It provides authentication, directory navigation, and bidirectional upload and download capabilities, making it the standard protocol for this function.

SMTP (Simple Mail Transfer Protocol) is used for relaying email messages between mail servers and is not designed for general-purpose text or binary file transfers.