Which of the following options is correctly matched?

The correct answer is Decomposers – Bacteria.

Let us analyze each pair based on ecological roles within an ecosystem:

1. Herbivores – Secondary consumers: Incorrect. Herbivores feed directly on green plants (producers), which makes them primary consumers.

2. Omnivorous – Green plants: Incorrect. Green plants synthesize their own food via photosynthesis and are classified as producers or autotrophs, not omnivores.

3. Carnivores – Primary consumers: Incorrect. Carnivores feed on herbivores (primary consumers), which makes them secondary or tertiary consumers.

4. Decomposers – Bacteria: Correct. Decomposers are organisms that break down dead organic matter and waste materials into simpler nutrients. Bacteria and fungi are classic examples of decomposers in an ecosystem.