Smog is formed from the mixture of pollutants in the atmosphere. Smog occurs when gases release from burning mixed with heat from sunlight. Its makes the environment unfavorable to live,smog could cause breathing problem for inhabitants or people.
Micro-organisms are not needed in the formation of smogs but gases hence the need to be exempted from the list.
Actually, Smog refers to heavily stagnant air formed by the mixture of nitrogen oxides with hydrocarbons released to the atmosphere from the exhaust of automobiles.
Thus, smog production is ABSOLUTELY A NON-ORGANIC process i.e it does not involve any activity of living organisms like microorganisms. So, all the processes mentioned above involved microorganisms EXCEPT SMOG PRODUCTION
