Pseudomonas is a

Options

A. Ammonifying bacteria
B. Nitrifying bacteria
C. Denitrifying bacteria
D. Nitrogen fixing bacteria

Explanation

**Step-by-Step Solution:**

1. **Understanding Pseudomonas**: Pseudomonas is a genus of bacteria that plays various roles in the nitrogen cycle. It is essential to identify its specific function among the options provided.

2. **Analyzing the Options**: The question provides four options:
- Ammonifying bacteria
- Nitrifying bacteria
- Denitrifying bacteria
- Nitrogen-fixing bacteria

3. **Defining Each Type of Bacteria**:
- **Ammonifying Bacteria**: These bacteria convert organic nitrogen from dead organisms into ammonia.
- **Nitrifying Bacteria**: These bacteria convert ammonia into nitrites and then into nitrates.
- **Denitrifying Bacteria**: These bacteria convert nitrates back into nitrogen gas, releasing it into the atmosphere.
- **Nitrogen-Fixing Bacteria**: These bacteria convert atmospheric nitrogen into ammonia.

4. **Identifying the Role of Pseudomonas**: Pseudomonas is known to be involved in the process of denitrification, where it reduces nitrates in the soil back to nitrogen gas.

5. **Conclusion**: Since Pseudomonas is involved in the conversion of nitrates to nitrogen gas, it is classified as a denitrifying bacteria.

6. **Final Answer**: Therefore, the correct answer is that Pseudomonas is a **denitrifying bacteria**.

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