Organism useful in degrading organic pollutants is

Options

A. Pseudomonas
B. Nitrosomonas
C. Chlamydia
D. Actinomycetes.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for an organism that is useful in degrading organic pollutants. This process is known as bioremediation.

2. **Defining Bioremediation**: Bioremediation is a biological process where living organisms, primarily microorganisms, are used to break down or remove pollutants from the environment, particularly organic pollutants.

3. **Identifying the Options**: The options given are:
- Pseudomonas
- Nitrosomonas
- Chlamydia
- Actinomycetes

4. **Analyzing Each Option**:
- **Pseudomonas**: This is a genus of bacteria known for its ability to degrade a wide range of organic pollutants, including hydrocarbons found in oil and industrial waste. They possess enzymes that facilitate the breakdown of these compounds.
- **Nitrosomonas**: This bacterium is involved in nitrification, a process that converts ammonia into nitrites. It does not play a role in degrading organic pollutants.
- **Chlamydia**: This is primarily known as a pathogen causing sexually transmitted infections and is not involved in bioremediation.
- **Actinomycetes**: Although these are beneficial soil bacteria, they are not primarily known for degrading organic pollutants.

5. **Conclusion**: Based on the analysis, the organism that is useful in degrading organic pollutants is **Pseudomonas**.

**Final Answer**: The correct answer is **Pseudomonas**.

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