Which term describes pollutants released by natural processes such as volcanic activity and wildfires?

• A. Industrial emissions
• B. Natural emissions
• C. Biogenic emissions
• D. Anthropogenic emissions

Answer: (B)

When pollutants come from natural processes that happen without human action, they’re described as natural emissions. Volcanoes release gases and particulates, and wildfires emit smoke and various gases as vegetation burns. These examples come from natural Earth processes, not human activity, so natural emissions is the best fit.

Industrial emissions and anthropogenic emissions refer to pollutants produced by humans—through factories, vehicles, energy use, and similar activities. Biogenic emissions come from living organisms, mainly certain gases released by plants, which is a biological source rather than geological or wildfire activity. So natural emissions correctly labels pollutants from volcanic activity and wildfires.