A bacterium which has been genetically modified tocontrol pollution is

Options

A. Pseudomonas
B. Rhizobium
C. Nitrobacter
D. Nitrosomonas.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a bacterium that has been genetically modified to control pollution. We need to evaluate the options provided: Pseudomonas, Rhizobium, Nitrobacter, and Nitrosomonas.

2. **Analyzing Each Option**:
- **Pseudomonas**: This bacterium is known for its role in bioremediation. It can degrade organic waste and some strains have been genetically modified to enhance their ability to control pollutants, such as oil spills.
- **Rhizobium**: This bacterium is primarily involved in nitrogen fixation, which is not directly related to pollution control.
- **Nitrobacter**: This bacterium is involved in the oxidation of ammonium to nitrite, which is part of the nitrogen cycle but does not relate to pollution control.
- **Nitrosomonas**: Similar to Nitrobacter, it is also involved in the oxidation of ammonium and is not related to pollution control.

3. **Identifying the Correct Answer**: Based on the analysis, Pseudomonas stands out as the bacterium that has been genetically modified for pollution control. It has the capability to degrade organic pollutants and some strains have been enhanced for this purpose.

4. **Conclusion**: The correct answer to the question is **Pseudomonas**.

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