What does a red traffic light signify?
A.Stop
B.Move fast
C.Slow down
D.None of the above

Hint:There are mainly three colors in a traffic light: red, yellow, and green. Each colour of the traffic light gives clear instructions to the people. These traffic signals are meant to control the traffic.

Complete step by step answer:
Option A) Red traffic light usually indicates to motorists that it is dangerous to ride ahead due to high traffic and signals to stop them at the position and tell them to wait until the traffic load is less. The vehicles are not allowed to turn at red sign unless there is a sign to it. Amber light signals to be ready to move ahead but not to drive immediately and wait for the green light signal which signals to move ahead as the traffic flow is handled and safe to drive.
Option B) Green light is used to signal that the traffic block has been cleared, or it is safe to move ahead and indicates to move fast.
Option C) Sign for slow down is yellow colour and is used mainly to avoid accidents. The accident prone areas use this sign and signals if there is a bump ahead, so that the motorists drive slowly and avoid any accidents. The sign is also placed near playgrounds showing that children are playing. It is made from heavy- duty aluminum for better visibility. This sign is also used if there is a nearby neighborhood or a pedestrian walking area.

Hence, the correct answer is option (A).

Note:
The red lights are used to send the signal to stop the motorists from driving. The colour red is chosen because of the highest visible wavelength of red colour, it has least scattering capacity and can be visible from far distance.