Most famous bacterial fertilizer is .

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the most famous bacterial fertilizer. This indicates that we need to identify a specific bacterium that plays a significant role in enhancing soil fertility.

2. **Identifying Bacterial Fertilizers**: Bacterial fertilizers are often associated with nitrogen-fixing bacteria, which help convert atmospheric nitrogen into a form that plants can use.

3. **Recognizing Key Bacteria**: Among the various nitrogen-fixing bacteria, *Rhizobium* is one of the most well-known. It forms a symbiotic relationship with leguminous plants.

4. **Symbiotic Relationship**: *Rhizobium* infects the roots of leguminous plants, leading to the formation of nodules. These nodules serve as sites for nitrogen fixation, where atmospheric nitrogen is converted into ammonia, which is then utilized by the plant.

5. **Conclusion**: Based on the information gathered, the most famous bacterial fertilizer is *Rhizobium*.

**Final Answer**: The most famous bacterial fertilizer is *Rhizobium*.

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