Question

the most important air pollutant source in the u.s. in terms of human health is select one: a. smoking. b. industrial waste. c. coal burning. d. car exhaust.

Explanation:

Smoking exposes individuals directly to a concentrated mix of harmful chemicals and is a major risk - factor for numerous health issues like lung cancer, heart disease etc. While industrial waste, coal burning, and car exhaust contribute to air pollution on a large - scale, smoking has a more immediate and direct impact on individual human health in the U.S.

Answer:

A. smoking