The name of the protocol that supports linking from one web page to another page is

Hypertext Transfer Protocol is the protocol that supports linking and moving between one web page and another.

HTML is the markup language for page content, not the transfer protocol that fetches links.

IP handles addressing and routing of packets, a lower layer than page-to-page linking.

FTP moves files between hosts and is not the protocol behind web-page hyperlinks.

HTTP defines requests like GET and responses that carry the linked page.

The secure version, HTTPS, adds TLS encryption to the same protocol.