Bacteria are essential in carbon cycle as:-

Options

A. Decomposer
B. Synthesizer
C. Consumer
D. Pri. Producer

Answer

### Step-by-Step Solution:

1. **Understanding the Carbon Cycle**: The carbon cycle is a biogeochemical cycle that involves the movement of carbon among the atmosphere, oceans, soil, plants, and animals. It is crucial for maintaining the balance of carbon in the environment.

2. **Role of Bacteria**: Bacteria, along with fungi, are classified as decomposers. They play a vital role in breaking down dead organic matter, which is primarily composed of carbon, hydrogen, oxygen, and nitrogen.

3. **Decomposition Process**: When living organisms (plants and animals) die, their bodies contain a significant amount of carbon. Decomposers like bacteria break down this organic matter, releasing carbon back into the soil and atmosphere.

4. **Carbon Release**: The carbon released during decomposition can be utilized by plants for photosynthesis, thus continuing the cycle. This process ensures that carbon is recycled in the ecosystem.

5. **Conclusion**: Therefore, bacteria are essential in the carbon cycle primarily as decomposers, facilitating the breakdown of organic matter and the release of carbon into the environment.

### Final Answer:
Bacteria are essential in the carbon cycle as decomposers.

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