( A ) At present it is not possible to grow maize without chemical fertilizers
( B ) Extensive use of chemical fertilizers may lead to eutrophication of nearby water bodies
( C ) Cyanobacteria such as Anabaena and nostoc are important mobilizers of phosphates and potassium for plant nutrition in soil
( D ) Both Azotobacter and Rhizobium fix atmospheric nitrogen in root nodules of plants
