Bacteria involved in production of methane gas are

Options

A. Actinomycetes
B. Methanogens
C. Methanotrophs
D. Cyanobacteria.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the type of bacteria involved in the production of methane gas.

2. **Analyzing the Options**:
- **Option 1: Actinomycetes**: These are unicellular, gram-positive, saprophytic bacteria that act as decomposers. They do not produce methane gas.
- **Option 2: Methanogens**: These bacteria are known for their ability to produce methane gas. They typically use carbon dioxide and organic compounds (like acetic acid) to produce methane, and they are commonly found in environments such as cow dung.
- **Option 3: Methanotrophs**: These bacteria do not produce methane; instead, they utilize methane as their source of carbon and energy.
- **Option 4: Cyanobacteria**: These are photosynthetic bacteria that primarily produce oxygen and do not play a role in methane production.

3. **Identifying the Correct Answer**: Based on the analysis, the bacteria involved in the production of methane gas are **methanogens**.

4. **Final Answer**: Therefore, the correct answer is **Option 2: Methanogens**.

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