Archaebacteria that live in marshy areas are

Options

A. Halophiles
B. Methanogens
C. Acidophiles
D. Cryophiles

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the type of Archaebacteria that inhabit marshy areas.

2. **Identifying the Class of Archaebacteria**: Among the various classes of Archaebacteria, we need to identify which one is specifically known for living in marshy or moist environments.

3. **Recognizing Methanogens**: The class of Archaebacteria that is known to thrive in marshy areas is called Methanogens.

4. **Characteristics of Methanogens**: Methanogens are primitive prokaryotic organisms that play a crucial role in the production of methane gas, commonly referred to as biogas.

5. **Conclusion**: Therefore, the Archaebacteria that live in marshy areas are known as Methanogens.

### Final Answer:
Archaebacteria that live in marshy areas are known as Methanogens.

---