Answer:
Option A, supplement signs, is the right answer.
Explanation:
The document which is used to particularize the standards by which traffic signs, road surface recognizing, and signals are created, fixed, and practiced, is known as the Manual on Uniform Traffic Control Devices. These specifications incorporate the colors, size, shapes and fonts applied in road markings and symbols.
With such signs, drivers can obtain more information about the roads they use. The information obtained plays a very significant role in making a journey best.
The 4 white lettering and symbols also provide real-time information about the road to the driver through which he can have a safe journey and avoid accidents.