Correct Answer:
A. Domain Name System
The correct answer is Domain Name System. DNS is a fundamental component of the internet that translates human-readable domain names (like example.com) into numerical IP addresses (like 192.0.2.1) that computers use to identify each other on a network. It acts like a phonebook for the internet.
- Defence Nuclear System is an unrelated term.
- Downloadable New Software is not an established acronym and does not relate to the function of DNS.
- Dependent Name Server is not the correct full form; while DNS involves name servers, 'Domain Name System' is the universally recognized term.