Biogas production is carried out by :

Options

A. Thermoacidophiles
B. Methanogens
C. Halophiles
D. Ruminants

Explanation

**Step-by-Step Solution:**

1. **Understanding Biogas**: Biogas is a mixture of gases produced by the breakdown of organic matter in the absence of oxygen (anaerobic digestion). The primary component of biogas is methane (CH₄), along with carbon dioxide (CO₂) and small amounts of other gases.

2. **Microbial Activity**: The production of biogas is facilitated by specific microorganisms that thrive in anaerobic conditions. These microorganisms decompose organic materials, leading to the generation of biogas.

3. **Identifying the Key Microbes**: The key group of bacteria responsible for the production of methane in biogas is called methanogens. These bacteria are specialized in breaking down organic matter and producing methane as a byproduct.

4. **Examples of Methanogens**: One of the well-known examples of methanogenic bacteria is Methanobacterium. These bacteria are crucial in the anaerobic digestion process and are commonly found in environments such as wetlands and the digestive tracts of ruminants.

5. **Analyzing the Options**:
- **Thermoacidophiles**: These are organisms that thrive in high temperature and low pH environments. They are not involved in biogas production.
- **Methanogens**: This is the correct answer as they are the bacteria that produce methane and thus biogas.
- **Halophiles**: These organisms live in high salt concentrations and are not related to biogas production.
- **Ruminants**: Ruminants are herbivorous mammals (like cows) that have a specialized stomach for digesting cellulose. They are not bacteria and do not directly produce biogas.

6. **Conclusion**: Based on the analysis, the correct answer to the question "Biogas production is carried out by:" is **Methanogens**.

**Final Answer**: Methanogens (Option B)

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