The correct answer is C. Data transmission.
Data transmission is the process of sending data from one place to another, by physical or electronic means. It is a fundamental part of modern communication and is used in a wide variety of applications, including telecommunications, computer networking, and data storage.
E-mail is a system for exchanging digital messages, typically consisting of text, images, or other attachments, sent from an author to one or more recipients via an electronic network such as the Internet.
The Internet is a global system of interconnected computer networks that use the standard Internet protocol suite (TCP/IP) to serve billions of users worldwide. It is a network of networks that consists of millions of private, public, academic, business, and government networks, of local to global scope, that are linked by a broad array of electronic, wireless, and optical networking technologies. The Internet carries an extensive range of information resources and services, such as the inter-linked hypertext documents and applications of the World Wide Web (WWW), electronic mail, telephony, and file sharing.
Distributed processing is a method of organizing and managing a computer system so that tasks are performed by multiple computers at the same time. This can be done in a number of ways, but the most common is to use a network of computers to share the workload. Distributed processing can be used to improve performance, reliability, and scalability.
None of the above is not the correct answer.