A. Open
B. Closed
C. Partially closed
D. None of the above

Solution

B. Closed

Explanation

<p><span style="font-size: 14px;">A closed-loop control system uses feedback to control its operation.</span></p><p><span style="font-size: 14px;">An automatic toaster senses the heat or time and adjusts the heating accordingly to toast the bread properly.</span></p><p><span style="font-size: 14px;">It may stop heating based on a timer, thermostat, or brownness sensor—this is feedback.</span></p>