What do cars, power plants and furnaces have in common?

(brainpop)

They all burn fossil fuel is the correct answer.

Explanation:

Cars, power plants, and furnaces all burn fossil fuels such as coal, natural gas, heavy oils, petroleum, oil.

Burning of these fossil fuels results in a release of a huge amount of carbon dioxide and sulfur dioxide gas, into the surrounding that causes air pollution, global warming, acid rain, and these gases present in the environment are highly corrosives and makes suffocating in the environment.