Final answer:
False. Registered users will not be able to log in to a deactivated PBX.
Step-by-step explanation:
False
Registered users will not be able to log in to a deactivated PBX because the PBX is no longer functioning. A PBX, or Private Branch Exchange, is a telephone system used within a company or organization. When a PBX is deactivated, it means that it has been turned off or shut down, and therefore, users cannot log in or access its services.