Consider a properly functioning positive feedback system whose output variable is not equal to plateau at 1:00 AM. At 1:00 AM,
A. when the value of threshold is greater than the value of the output variable, then the value of the output variable always increases to the value of the plateau.
B. a change in the value of the actuating signal will lead to a change in the output of the effector.
C. the sensor measures the current value of the output variable.