Most famous nitrogen fixing bacterium/biofertilizer is

The main sources of biofertilisers are

$(a)$ Bacteria
$(b)$ Cyanobacteria
$(c)$ Fungi
$(d)$ Protists

Which of the following is free living aerobic and nonphotosynthetic nitrogen fixing bacterium

Which of the following is used as biofertiliser?

$I.$ Cyanobacteria

$II.$ Yeast

$III.$ Symbiotic bacteria

$IV.$ Free living bacteria

Choose the correct option

Mycorrhiza represents

Which one of the following is not a biofertiliser?