Which one of the following statements is correct?

1. Both Azotobacter and Rhizobium fix atmospheric nitrogen in root nodules of plants.
2. Cyanobacteria such as Anabaena and Nostoc are important mobilizers of phosphates and for plant nutrition in soil
3. At present it is not possible to grow maize without chemical fertilizers
4. Extensive use of chemical fertilizers may lead to eutrophication of nearby water bodies.

Extensive use of chemical fertilizers may lead to eutrophiction of nearby water bodies.