Which term is information returned to control or adjust a system?

• A. Feedback
• B. Sensor
• C. Input
• D. Process

Answer: (A)

Feedback is information about the system’s output that is used to adjust its operation. In a closed-loop control setup, the actual result is measured and that measurement is fed back to the controller, which compares it to the desired value and makes changes to reduce any error. This keeps things like temperature, speed, or position steady and accurate. For example, a thermostat uses a sensor to read the room temperature and then decides whether to turn the heater on or off; the outcome is fed back to influence future decisions. A sensor provides the data, but the term describing the information returned to control the system is feedback. An input is what you feed into the system to drive it, and a process is the set of actions that transform inputs into outputs.