正解:B
Explanation
A physical diagram is a type of diagram that shows the physical layout and connections of the network devices and components, such as routers, switches, cables, and connectors. A physical diagram may include specifications about the fiber connector types, such as LC, SC, FC, ST, MPO, etc., that are used to link the fiber optic cables and devices. A physical diagram can help to visualize the network topology, troubleshoot network problems, and plan network changes