Which protocol provides secure file transfer over an encrypted connection?

Secure File Transfer Protocol (SFTP) is specifically designed to provide secure file transfer capabilities by utilizing encryption. This ensures that data transferred over a network is protected from eavesdropping or tampering. SFTP operates over a secure shell (SSH) connection, which encrypts both the command and data channels, providing integrity and confidentiality.

In contrast to the other options, File Transfer Protocol (FTP) does not offer encryption, making it vulnerable to security risks. Dynamic Host Control Protocol (DHCP) is used for assigning IP addresses dynamically within a network but does not pertain to file transfers. HyperText Transfer Protocol (HTTP) is used for transmitting web pages but lacks built-in security features to protect data during transmission. Thus, Secure File Transfer Protocol is the correct answer as it fulfills the requirement for secure and encrypted file transfer.