Concept:A server is a network computer that stores and shares resources with client devices.
Explanation:A server acts as a central hub on a network.
It provides hardware, software, and other services to many connected clients.
Mainframes handle large-scale processing, but they are not defined as central network resource providers.
Workstations are built for individual use, not shared services.
Supercomputers focus on extremely complex computations, not resource distribution.
Only the server matches the role described in the question.
Answer:D. Server