The process of breaking down organic matter by microorganisms is called?

Correct answer: (c) Decomposition

Explanation

Decomposition is the breakdown of dead organic matter by microorganisms into simpler substances.

Decomposers like bacteria and fungi release inorganic nutrients (nitrogen, phosphorus, CO₂) back to the environment.

Respiration releases energy in living cells, photosynthesis makes food, and fermentation is anaerobic breakdown of sugars – not general decay of organic matter.