A telephone switch located on a company’s property with a direct connection to the phone company’s central office is called a:

A.
Hub

B.
PBX

C.
Router

D.
BPX

Explanation:
A private branch exchange (PBX) is a device used within companies to
provide multiple services to users throughout a building or facility. There are
several security concerns pertaining to PBX; default configurations and passwords
should be changed, maintenance modems should only be enabled when used, phone bills
should be continually reviewed, and unused codes should be disabled.