Which is not a harmful effect of loss of biodiversity? a) loss of predators means an increase in pest populations b) water purification is hindered c) the hole in the ozone increases d) soil formation is impaired

I think the correct answer would be that soil formation is impaired. It would have not that big of an impact to the society as compared to the other choices. Increase of pest populations would surely affect agriculture. Hindered water purification would affect the quality of groundwater. Also, increasing hole in the ozone surely affect everyone. 

Bidk