All of the Following Statements About Carbon Monoxide (CO)pollution in the United

Multiple Choice

All of the following statements about carbon monoxide (CO) pollution in the United States are true EXCEPT

A) carbon monoxide makes up over 60% (by mass) of all air pollutants emitted into the atmosphere.
B) the concentration of carbon monoxide is higher in urban areas than in rural areas.
C) people exposed to carbon monoxide have a higher risk of heart attacks.
D) the major source of carbon monoxide emissions is industrial sources, such as metal processing.