Asteady circular light means drivers must stop at a marked stop line. a. green b. red c. yellow d. non of above

b. RED

Explanation:

As we know that traffic signals are used to control the movement of traffic so that it is controlled.

Now we know that there must be a specific signal that people will know so that traffic must be controlled.

Here different colors have specific meaning which is given as

RED : Stop at the signal

YELLOW : Slow down or ready to move

GREEN : You can move the vehicle

so here as per this signal rule we can say that RED color signal means the driver has to stop at the stop line