Question

Vehicles account for most of the ______.

Options

• carbon monoxide

• nitrogen oxides

• particulates

• carbon dioxide

Answer 1

Vehicles account for most of the carbon monoxide.

Explanation:

Vehicles are major sources of carbon monoxide (CO), a colorless, odorless gas produced by the incomplete combustion of fuel in engines. This gas is highly toxic and is most commonly emitted from cars, trucks, and buses. While vehicles also emit carbon dioxide, nitrogen oxides, and particulates, carbon monoxide is the most dominant pollutant from motor vehicles.