The correct answer is: A. Hypertext Transfer Protocol
HTTP stands for Hypertext Transfer Protocol. It is an application-level protocol that defines how messages are formatted and transmitted between a web server and a web browser. HTTP is the foundation of the World Wide Web, and it is used to transfer hypertext documents, such as HTML pages, images, and videos.
The other options are incorrect. Option B, Hypertext Transfer Plotter, is not a real protocol. Option C, Head Tail Transfer Plot, is a nonsense phrase. Option D, Head Tail Transfer Protocol, is a similar nonsense phrase. Option E, None of these, is also incorrect, as HTTP is a real protocol.