An officer is swinging a red or yellow light — what does this require?

An officer is swinging a red or yellow light — what does this require?
A)To pass on the side corresponding to the arm giving the signal.
B)To reduce speed.
C)To stop vehicles toward which the light is directed.Correct
An officer swinging a red or yellow light requires road users toward whom the officer directs the light to stop.
Do not confuse this with when the officer, with arm extended, moves it alternately up and down. In that case, it requires drivers approaching the officer from the side corresponding to the arm giving the signal to reduce their vehicle's speed, perpendicular to that arm.