Which protocol is primarily used to transfer files between a client and a server?

• A. DNS
• B. DHCP
• C. NAT
• D. FTP

Answer: (D)

Transferring files between a client and a server is what FTP is designed for. FTP provides commands to log in, navigate directories, and upload or download files, and it uses reliable TCP to ensure data arrives intact. It works with a control connection for commands and a separate data connection for the actual file transfer, which helps manage the transfer process and supports different transfer modes (like text or binary). This direct focus on file movement and management makes FTP the natural choice for moving files between a client and a server. The other options handle addressing or routing tasks—DNS translates domain names to IPs, DHCP assigns IP addresses, and NAT translates private IPs to public addresses—rather than transferring files.