The correct answer is: A. HTTP
HTTP stands for Hypertext Transfer Protocol. It is a set of rules that allow computers to communicate with each other over the internet. HTTP is used to transfer data between a web server and a web browser. When you visit a website, your web browser sends a request to the web server using HTTP. The web server then sends the requested web page back to your web browser.
TCP/IP stands for Transmission Control Protocol/Internet Protocol. It is a set of rules that allow computers to communicate with each other over the internet. TCP/IP is responsible for routing data between computers.
FTP stands for File Transfer Protocol. It is a set of rules that allow computers to transfer files to and from each other over the internet. FTP is used to upload and download files from websites.
SMTP stands for Simple Mail Transfer Protocol. It is a set of rules that allow computers to send and receive email. SMTP is used by email servers to deliver email messages to their recipients.
In conclusion, HTTP is the protocol that is used for the World Wide Web. It is used to transfer data between web servers and web browsers.