Central direct digital control system is a control system in which all decisions are made in one location and that provides closed loop control. Which option correctly describes this type of system?

• A. Decisions are made at multiple locations with no central authority.
• B. Operates using open-loop control without feedback.
• C. Requires separate gateways for each subsystem.
• D. All decisions are made in one location and it provides closed loop control.

Answer: (D)

Centralized, direct digital control means one main controller handles every decision in a single location and uses feedback from the process to adjust its outputs, forming a closed-loop system. This single-point decision-making enables the controller to continuously monitor sensors, compute the appropriate control signals, and drive actuators to keep the process on target. The other descriptions don’t fit because they describe distributed decision-making without central authority, open-loop behavior that lacks feedback, or network architectures (like separate gateways) that aren’t defining features of a central, closed-loop digital controller.