正解:B,C
A server provides services to clients. In practical network terms, it runs applications or services that workstations request, and it can handle requests from multiple clients at the same time. Examples include web servers, file servers, DNS servers, DHCP servers, authentication servers, and application servers. A server does not have to run the same operating system as other servers to communicate; network protocols provide interoperability. It also does not achieve redundancy only through virtual clustering, and it does not have to be housed solely in a data center dedicated to one client. Cisco CCNA 200-301 v1.1 Network Fundamentals includes endpoint and server roles because engineers must understand what traffic sources and destinations exist on the network. The two correct functions are application/data service delivery and handling simultaneous client requests. That makes B and C correct.