Which of the following statements about air pollution are FALSE?
I. Natural sources of particle air pollution include volcanic eruptions and dust storms.
II Emissions have been reduced in the US because of federal policies, cleaner-burning engines and technologies such as scrubbers that control sulfur in exhaust from power plants.
III Under current law, when a state does not comply with federal regulations involving air pollution, the EPA can take over enforcement of the regulations.
IV. Photochemical smog forms when sunlight drives chemical reactions between primary pollutants and atmospheric compounds.

A. I and III
B. II and IV
C. I, III and IV
D. None of the above