Bacterium Pseudomonas is useful as it can

Options

A. Transfer gene from one plant to another plant
B. Fix atmospheric nitrogen
C. Decompose a variety of organic compounds
D. Produce several antibiotics

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the usefulness of the bacterium Pseudomonas and provides four options to choose from.

2. **Analyzing Each Option**:
- **Option 1**: "Transfer gene from one plant to another plant" - This option describes the role of vectors in genetic engineering. Pseudomonas is not a vector, so this option is incorrect.

- **Option 2**: "Fix atmospheric nitrogen" - Nitrogen-fixing bacteria are typically from the genera Rhizobium or Azotobacter. Pseudomonas does not have this capability, making this option incorrect as well.

- **Option 3**: "Decompose a variety of organic compounds" - Pseudomonas is known for its ability to decompose organic materials, including agricultural waste, and it plays a significant role in the ecosystem by recycling nutrients. This option is correct.

- **Option 4**: "Produce several antibiotics" - While some bacteria produce antibiotics, Pseudomonas is not primarily known for this function, so this option is incorrect.

3. **Conclusion**: Based on the analysis, the correct answer is that Pseudomonas is useful because it can decompose a variety of organic compounds.

**Final Answer**: Pseudomonas is useful as it can decompose a variety of organic compounds.

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