Answer: C) Prokaryotes convert nitrogen-containing molecules into forms that can't be used by other organisms.
Prokaryotes are the organisms that do not have a membrane bound nucleus, mitochondria and other organelle. They ranges in size of diameter from 0.1–5.0 µm.
Example: Escherichia coli, Sulfolobus acidocaldarius archeobacterium
Decomposers, play an important role in nitrogen cycle. Nitrogen gas is converted to nitrate compound by nitrogen fixing bacteria which are present in root nodules of leguminous plants.
Example: Azotobacter
