Biogas is mainly formed of

Options

A. `CH_(4)`
B. `O_(2)`
C. `N_(2)`
D. `CO_(2)`

Explanation

**Step-by-Step Solution:**

1. **Understanding Biogas Composition**: Biogas is primarily a mixture of gases produced through the anaerobic decomposition of organic matter. The main components of biogas include methane, carbon dioxide, hydrogen sulfide, and hydrogen.

2. **Identifying the Main Component**: Among these gases, methane (CH₄) is the most significant component, making up a large percentage of biogas. It is the main gas that is utilized for energy production.

3. **Role of Microbes**: The production of biogas, particularly methane, is facilitated by a specific group of bacteria known as methanogens. These bacteria thrive in anaerobic (oxygen-free) environments and are crucial for the breakdown of organic materials.

4. **Anaerobic Decomposition Process**: In the absence of oxygen, complex organic materials, such as those found in animal dung (especially from ruminant animals like cows and buffaloes), are decomposed by methanogens. This process converts these materials into simpler substances, resulting in the formation of biogas.

5. **Conclusion**: Therefore, the main gas in biogas is methane, which is produced through the anaerobic decomposition of organic matter by methanogenic bacteria.

**Final Answer**: Biogas is mainly formed of methane.

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