Which of the following are found in extreme saline conditions?

Options

A. Archaebacteria
B. Eubacteria
C. Cyanobacteria
D. Mycobacteria

Answer

To determine which of the following organisms are found in extreme saline conditions, we need to analyze each option provided: Archaebacteria, Eubacteria, Cyanobacteria, and Mycobacteria.

### Step-by-Step Solution:

1. **Understanding Archaebacteria**:
- Archaebacteria are simple prokaryotic organisms that can survive in extreme environments. They are known as extremophiles because they thrive in harsh conditions, including extreme salinity, temperature, and acidity.
- **Conclusion**: Archaebacteria are found in extreme saline conditions.

2. **Analyzing Eubacteria**:
- Eubacteria are also prokaryotic but are more common and diverse than Archaebacteria. They can be found in various environments, but they are not specifically adapted to extreme saline conditions.
- **Conclusion**: Eubacteria are generally not found in extreme saline conditions.

3. **Examining Cyanobacteria**:
- Cyanobacteria are photosynthetic bacteria that can be found in a variety of environments, including freshwater and marine ecosystems. While some species can tolerate saline conditions, they are not specifically adapted to extreme salinity.
- **Conclusion**: Cyanobacteria are not primarily found in extreme saline conditions.

4. **Looking at Mycobacteria**:
- Mycobacteria are a group of bacteria that are primarily known for their pathogenic species, such as those causing tuberculosis and leprosy. They do not have adaptations to thrive in extreme saline environments.
- **Conclusion**: Mycobacteria are not found in extreme saline conditions.

### Final Answer:
Based on the analysis, the organism that is found in extreme saline conditions is **Archaebacteria**.

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