The correct answer is: B. Communication service.
Electronic mail (email) is a method of exchanging digital messages from one computer user to another over a computer network. A user typically has an email address which is a unique identifier that identifies the user’s email account. Email addresses are usually written in the form of “username@hostname”.
Email is a communication service because it allows users to send and receive messages from each other. It is a very popular service, and it is used by people all over the world.
The World Wide Web (WWW) is a system of interlinked hypertext documents accessed via the Internet. With a web browser, one can view web pages that may contain text, images, videos, and other multimedia and navigate between them using hyperlinks.
Information retrieval services are services that allow users to search for and retrieve information from a variety of sources, including the Internet.
Web services are a set of standards that allow software applications to communicate with each other over the Internet.
I hope this helps!