Question

what is an example of a mobile source of air pollution?
automobile
power plants
industrial furnace
landfill site

Explanation:

Mobile sources of air pollution are those that can move. Automobiles are vehicles that can move from one place to another and emit pollutants like carbon monoxide, nitrogen oxides, etc. Power plants, industrial furnaces, and landfill sites are stationary sources as they are fixed at one location.

Answer:

automobile