The answer is "c. water".
Water is not a atmospheric pollutant.
Atmospheric pollutants are substances that gather in the air all around to a degree that is unsafe to living life forms or to materials presented to the air. Basic air toxins incorporate smoke , brown haze , and gases, for example, carbon monoxide , nitrogen and sulfur oxides, and hydrocarbon vapor. While vaporous poisons are by and large undetectable, solid or liquid pollution in smoke and exhaust cloud are effectively observed. One especially poisonous type of air contamination happens when oxides of sulfur and nitrogen consolidate with air dampness to create sulfuric and nitric corrosive . At the point when the acids are conveyed to Earth as corrosive rain , harm is perpetrated on lakes, streams, vegetation, structures, and different items. Since sulfur and nitrogen oxides can be conveyed for long separations in the climate before they are expelled in precipitation, harm may happen a long way from pollution sources.