mixing of pollutants with rain erosion of topsoil by clearcutting runoff of fertilizer used in farming thinning of the atmospheric ozone layer
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Some plant species are more tolerant of acidic soil than others. The tolerant species are favored in areas affected by which consequence of human activity?
Possibilities:
- mixing of pollutants with rain
- erosion of topsoil by clearcutting
- runoff of fertilizer used in farming
- thinning of the atmospheric ozone layer

mixing of pollutants with rain