Light is refracted by water vapor in the air. Light is scattered by water droplets in the air. Light is absorbed by water vapor near the ground. Light is reflected by water droplets on the ground.
I gave my students this multiple choice question: In clear weather, a bright light can be seen for a long distance. In conditions of heavy fog, the visibility is greatly reduced. Which of the following explains the reduced visibility?

Only one answer is correct among these 4 choices:
- Light is refracted by water vapor in the air.
- Light is scattered by water droplets in the air.
- Light is absorbed by water vapor near the ground.
- Light is reflected by water droplets on the ground.

Could you tell me which one is correct?

Light is scattered by water droplets in the air.