Cyanobacteria and blue green algae are commonly called as nitrogen fixers. They increase the fertility of soil. How do these nitrogen fixers increase the
soil fertility?
(a) The produce nitrogen gas that is released into the surrounding.
(b) They convert nitrogen gas present in the surrounding into compost.
(c) The fix atmospheric nitrogen to make nitrogen compounds in the soil.
(d) They decompose remains of plants and animals to produce nitrogen
compounds.