The most abundant photochemical pollutant in smog is_?
Smog is a kind of air pollution, originally named for the mixture of smoke and fog in the air. The term "smog" was first used in London during the early 1900's to describe the combination of smoke and fog. Smog-forming pollutants come from many sources, such as automobile exhausts, power plants, factories, and many consumer products, including paints, hair spray, charcoal starter fluid, solvents etc.
This question is a part of GKToday's Integrated IAS General Studies Module