Archaebacteria of marshy habitats are :

Options

A. capable of converting `CO_(2)` into methane
B. chemoheterophic
C. explotied commercially in biogas production
D. more than one option is correct

Answer

**Step-by-Step Solution:**

1. **Understanding Archaebacteria**:
- Archaebacteria are a group of microorganisms that are distinct from bacteria and eukaryotes. They are known for their ability to thrive in extreme environments, such as marshy habitats.

2. **Identifying the Type of Archaebacteria in Marshy Habitats**:
- In marshy habitats, the predominant type of Archaebacteria are methanogens. Methanogens are specialized microorganisms that produce methane as a metabolic byproduct.

3. **Analyzing the Options**:
- **Option A**: "Capable of converting carbon dioxide into methane."
- This statement is correct. Methanogens reduce carbon dioxide to produce methane.
- **Option B**: "Chemolithotrophic."
- This statement is incorrect. Methanogens are not classified as chemolithotrophs; they are classified as chemo-autotrophs since they obtain energy from chemical reactions involving carbon compounds.
- **Option C**: "Exploited commercially in biogas production."
- This statement is correct. Methanogens are indeed exploited for biogas production, which is a renewable energy source.
- **Option D**: "All of the above."
- Since not all statements are correct, this option is incorrect.

4. **Conclusion**:
- The correct options regarding Archaebacteria of marshy habitats are A and C. Therefore, the best answer would be that they are capable of converting carbon dioxide into methane and are exploited commercially in biogas production.

**Final Answer**: Methanogens are the Archaebacteria of marshy habitats that convert carbon dioxide into methane and are exploited commercially in biogas production.

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