Engineers design a system for heating the air in a house. They want the
heater to bring the temperature to a comfortable level and then maintain it.
Which option describes how the engineers should design the system?
O A. Include a control in the system that senses the air temperature
and causes negative feedback, reducing the output of the heater.
O B. Design the system with a control that maintains a constant level of
output from the heater.
C. Include a control in the system that varies the input level in a
regular cycle.
Design the system with a control that allows positive feedback to
enhance the heating ability of the system,