D) can only perform one function on a network.
This statement is not true in this case.
In computing, a server is a computer program or a device that provides functionality for other programs or devices, called "clients". This architecture is called the client–server model. Servers can provide various functionalities, often called "services", such as sharing data or resources among multiple clients, or performing computation for a client. A single server can serve multiple clients, and a single client can use multiple servers. A client process may run on the same device or may connect over a network to a server on a different device.
For Further reading go to https://en.wikipedia.org/wiki/Server_(computing)