`N_2` - fixing bacteria in non-legume plants are:

Options

A. Frukia
B. Rhizobia
C. Plasmodium
D. Aspergillus

Explanation

To answer the question about nitrogen-fixing bacteria in non-legume plants, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Nitrogen Fixation**:
- Nitrogen fixation is the process of converting atmospheric nitrogen (N₂) into ammonia (NH₃), which plants can utilize. This process is essential because atmospheric nitrogen is not directly usable by most plants.

2. **Role of Prokaryotes**:
- Prokaryotes, particularly certain bacteria, possess an enzyme called nitrogenase that enables them to convert atmospheric nitrogen into a form that plants can absorb and use.

3. **Types of Nitrogen-Fixing Bacteria**:
- There are two main types of nitrogen-fixing bacteria:
- **Symbiotic Nitrogen-Fixing Bacteria**: These bacteria form a symbiotic relationship with plants, such as legumes. An example is Rhizobia, which specifically associates with leguminous plants.
- **Free-Living Nitrogen-Fixing Bacteria**: These bacteria do not require a host plant to fix nitrogen. Examples include Azotobacter and Anabaena.

4. **Identifying the Correct Bacteria**:
- The question specifically asks for nitrogen-fixing bacteria in non-legume plants. Among the options provided:
- **Franciae** is known to fix nitrogen in non-leguminous plants.
- **Rhizobia** is associated with legumes, not non-legumes.
- **Plasmodium** is a protozoan that causes malaria and is not involved in nitrogen fixation.
- **Aspergillus** is a fungus and does not fix nitrogen.

5. **Conclusion**:
- Therefore, the correct answer to the question is **Franciae**, as it is the nitrogen-fixing bacteria that can associate with non-legume plants.

### Final Answer:
The nitrogen-fixing bacteria in non-legume plants are **Franciae**.

---