Answer:
C.
Explanation:
Nitrogen fixation is a process by which molecular nitrogen in the air is converted into ammonia or related nitrogenous compounds in soil. Atmospheric nitrogen is molecular dinitrogen, a relatively nonreactive molecule that is metabolically useless to all but a few microorganisms.
It would be the respiratory system
Answer:
It means the entire variability among living organisms. From marine and terrestrial life forms, it also means that each types of these ecosystems hold large diverse species that have even their own subspecies.
Hey,
option (C) is right ...