Answer;
Colloid
Fog is a colloid composed of water droplets in air.
Step-by-step explanation;
-Fog is made up of condensed water droplets which are the result of the air being cooled to the point where it can no longer hold all of the water vapor it contains.
-A colloid is a heterogeneous mixture in which the dispersed particles are intermediate in size between those of a solution and a suspension. A fog is an example of a colloid as a beam of light can be easily seen passing through it.