Halophiles, methanogens and thermoacidophils are

Options

A. Cyanobacteria
B. Euhacteria
C. Actinomycetes
D. Archacbacteria

Answer

**Step-by-Step Solution:**

1. **Identify the Groups**: The question lists three groups: Halophiles, Methanogens, and Thermoacidophiles.

2. **Classification**: These groups need to be classified into the appropriate category. They are known for thriving in extreme environments.

3. **Understanding Halophiles**: Halophiles are organisms that thrive in high-salt environments, such as salt lakes or salt mines.

4. **Understanding Methanogens**: Methanogens are microorganisms that produce methane as a metabolic byproduct. They are commonly found in anaerobic environments, such as the guts of ruminant animals.

5. **Understanding Thermoacidophiles**: Thermoacidophiles are organisms that thrive in hot and acidic environments, such as hot springs.

6. **Common Characteristics**: All three groups share a common characteristic of being extremophiles, which means they can survive in extreme conditions that would be inhospitable to most other life forms.

7. **Taxonomic Classification**: These three groups are classified under the domain Archaea, specifically within the kingdom Monera.

8. **Conclusion**: Therefore, Halophiles, Methanogens, and Thermoacidophiles belong to the category of Archaebacteria.

**Final Answer**: Halophiles, Methanogens, and Thermoacidophiles are classified as Archaebacteria.

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