Which of the following is a bacterium?

-✅Explanation: This is a genus of bacteria that is involved in the nitrification process. It oxidizes ammonia to nitrite, playing a crucial role in the nitrogen cycle.
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📌Other Options Explanations:
-(a) Aspergillus: This is a genus of fungi. It includes species that can cause infections in humans and are used in the production of food and industrial processes.
-b) Penicillium: This is also a genus of fungi, known for producing the antibiotic penicillin.

🛑 Additional Information::
Nitrosomonas-
-Is also known as nitrifying bacteria.
-Nitrosomonas bacteria helps in the process of nitrification.
-In this process ammonia is oxidised to nitrate by the soil bacterium Nitrosomonas.