A farmer found out that the soil nitrogen levels in his field are extremely low. Which natural method will help the farmer to replenish the nitrogen content?

Options

A. Growing grass
B. Growing pea plants
C. Growing potato plants
D. Not growing any plants

Answer

To address the question of how a farmer can replenish the nitrogen content in his soil, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Problem**: The farmer has low nitrogen levels in his soil. Nitrogen is essential for plant growth and is a key component of proteins and nucleic acids.

2. **Understand Nitrogen Sources**: Nitrogen in the soil can be replenished through various methods, including chemical fertilizers and natural processes. However, the question specifically asks for a natural method.

3. **Consider Biological Nitrogen Fixation**: One of the natural methods to increase nitrogen levels in the soil is through biological nitrogen fixation. This process involves certain bacteria that convert atmospheric nitrogen into a form that plants can use.

4. **Identify Nitrogen-Fixing Plants**: Leguminous plants, such as peas, beans, and soybeans, have a symbiotic relationship with nitrogen-fixing bacteria (like Rhizobium) that reside in their root nodules. These bacteria help in fixing nitrogen from the atmosphere.

5. **Choose the Best Option**: Among the options provided (growing grass, growing pea plants, growing potato plants, not growing any plants), the best choice for replenishing nitrogen naturally is to grow pea plants (or other legumes).

6. **Conclusion**: The farmer should grow pea plants in his field to naturally replenish the nitrogen content in the soil.

### Final Answer:
The farmer can replenish the nitrogen content in his soil by growing pea plants.

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