Organisms that often bloom in polluted water bodies

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for organisms that bloom in polluted water bodies. This indicates we are looking for organisms that thrive in environments with high levels of pollution.

2. **Analyzing the Options**: The options provided are:
- Archaebacteria
- U-bacteria (Eubacteria)
- Mycoplasma
- Cyanobacteria

3. **Evaluating Archaebacteria**:
- Archaebacteria are known to thrive in extreme conditions such as high salinity and extreme temperatures. They do not typically flourish in polluted water, which does not provide the extreme conditions they require.

4. **Evaluating U-bacteria (Eubacteria)**:
- Eubacteria encompass a wide range of bacteria, but not all types are specifically known for blooming in polluted water. While some may tolerate pollution, they are not the primary organisms associated with such conditions.

5. **Evaluating Mycoplasma**:
- Mycoplasma are the smallest prokaryotic organisms and lack a cell wall. They are not typically found in polluted water bodies as they do not thrive in such environments.

6. **Evaluating Cyanobacteria**:
- Cyanobacteria are photosynthetic bacteria that can thrive in various environments, including polluted water. They are known to bloom in nutrient-rich waters, particularly when there are high levels of nitrogen and phosphorus, which are common in polluted water bodies.

7. **Conclusion**: Based on the analysis, the organism that often blooms in polluted water bodies is **Cyanobacteria**.

**Final Answer**: Cyanobacteria

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