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 prokaryotic microorganisms that are distinct from bacteria and eukaryotes. They are known for their ability to thrive in extreme environments.

2. **Types of Archaebacteria**: There are three main types of archaebacteria:
- **Halophiles**: These organisms thrive in highly saline environments, such as salt lakes.
- **Thermophiles**: These archaebacteria live in extremely hot environments, such as hot springs.
- **Methanogens**: These are the archaebacteria that are specifically found in marshy habitats and are known for their ability to produce methane.

3. **Methanogens in Marshy Habitats**: The question specifically refers to archaebacteria found in marshy habitats, which are methanogens. They convert carbon dioxide (CO2) into methane (CH4) through a process called methanogenesis.

4. **Commercial Exploitation**: Methanogens are exploited commercially for biogas production. Biogas is a renewable energy source that is produced from the anaerobic digestion of organic matter, and it primarily consists of methane.

5. **Evaluating the Options**: The question states that more than one option is correct regarding the capabilities of archaebacteria in marshy habitats. Since methanogens can convert CO2 into methane and are involved in biogas production, both statements are true.

6. **Conclusion**: Therefore, the correct answer to the question is that more than one option is correct, specifically related to the capabilities of methanogens in marshy habitats.

**Final Answer**: The archaebacteria of marshy habitats are methanogens, which are capable of converting CO2 into methane and are exploited commercially in biogas production. Thus, the correct option is D: more than one option is correct.

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