Bacteria utilised in gobar gas plants are
(a) Methanogens
(b) Nitrifying
(c) Anmonifying
(d) Denitrifying

Options

A. Methanougens
B. Nitrifying
C. Anmonifying
D. Denitrifying

Answer

To solve the question regarding the type of bacteria utilized in gobar gas plants, we will follow these steps:

### Step-by-Step Solution:

1. **Understand the Context**: Gobar gas plants utilize bacteria to produce biogas through a process known as anaerobic fermentation. This process occurs in the absence of oxygen.

2. **Identify the Options**:
- (a) Methanogens
- (b) Nitrifying
- (c) Ammonifying
- (d) Denitrifying

3. **Analyze Each Option**:
- **Methanogens**: These are a type of bacteria that produce methane gas and thrive in anaerobic conditions. They are essential for the anaerobic fermentation process that occurs in gobar gas plants.
- **Nitrifying Bacteria**: These bacteria are involved in the process of nitrification, which requires oxygen and is not related to the production of biogas.
- **Ammonifying Bacteria**: These bacteria convert organic nitrogen into ammonia, which is part of the nitrogen cycle but does not contribute to biogas production.
- **Denitrifying Bacteria**: These bacteria convert nitrates into nitrogen gas, again a process related to the nitrogen cycle and not to anaerobic fermentation.

4. **Conclusion**: Since the question specifically asks for the type of bacteria used in gobar gas plants, the correct answer is **(a) Methanogens**. They are the only bacteria listed that are involved in the anaerobic fermentation process necessary for producing gobar gas.

### Final Answer:
**(a) Methanogens**

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