The correct option is C Provides specific nutrients in high concentrations
A biofertiliser improves the nutrient quality of the soil in general in a natural setting. It does not change the chemical nature of soil. It does not cause water pollution like conventional chemical fertilisers do. Hence extensive use of biofertilisers does not result in eutrophication. However, unlike chemical fertilisers, biofertilisers do not provide specific nutrients at high concentrations.