Respuesta :
Correct answer: Oil and coal
Air pollution is caused mainly by the burning of fossil fuel, which include coal and oil. When coal is burned it releases a large number of airborne pollutants and toxins in the environment. It includes sulfur dioxide, nitrogen oxides, mercury and lead, and various other metals.
Carbon dioxide is considered as a good indicator of how much fossil fuel is burnt and how much of pollutant is released into the atmosphere.
