The archaebacteria occurring in marshes, swamps, rumens of catties, gobar gas plants are

Options

A. methanogens
B. ammonifying bacteria
C. thermoacidophiles
D. denitrifying bacteria

Answer

To solve the question regarding the archaebacteria occurring in marshes, swamps, rumens of cattle, and gobar gas plants, we will analyze the options provided one by one.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the type of archaebacteria found in specific environments such as marshes, swamps, rumens of cattle, and gobar gas plants.

2. **Evaluating the Options**:
- **Option A: Methanogens**:
- Methanogens are a type of archaebacteria that produce methane gas by decomposing organic matter under anaerobic (low oxygen) conditions. They are commonly found in environments like marshes, swamps, and the rumen of cattle, where organic matter is abundant and oxygen is limited. They are also utilized in gobar gas plants for biogas production.

- **Option B: Ammonifying Bacteria**:
- Ammonifying bacteria are involved in the process of ammonification, where they convert organic nitrogen into ammonia. While they play a role in nitrogen cycling, they are not specifically associated with the environments mentioned in the question.

- **Option C: Thermoacidophiles**:
- Thermoacidophiles are bacteria that thrive in extreme conditions of high temperature and low pH. They are not typically found in marshes or swamps.

- **Option D: Denitrifying Bacteria**:
- Denitrifying bacteria convert nitrates into nitrogen gas, thus playing a role in the nitrogen cycle. However, they are not specifically linked to the environments listed in the question.

3. **Conclusion**: After evaluating all the options, it is clear that **Option A: Methanogens** is the correct answer. Methanogens are indeed the archaebacteria that occur in marshes, swamps, rumens of cattle, and gobar gas plants.

### Final Answer:
The archaebacteria occurring in marshes, swamps, rumens of cattle, and gobar gas plants are **Methanogens**.

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