Complete the following cycle by labelling A-D and answer the given questions.
(i) What will happen, if step D does not occur?(ii) State two free-living nitrogen-fixing bacteria.
A - Ammonification B - NitritesC— Nitrates D — Denitrification (i) If step D does not occur then there will be no replenishment of atmospheric nitrogen. (ii) Azotobacter and Clostridium.