Which of the following crops would enrich the soil with nitrogen ?

Options

A. apple
B. pea
C. paddy
D. potato

Answer

### Step-by-Step Solution:

1. **Understand the Question**: The question asks which crop would enrich the soil with nitrogen. This indicates that we need to identify a crop that has the ability to add nitrogen to the soil.

2. **Identify Nitrogen-Fixing Crops**: Crops that enrich the soil with nitrogen are typically from the leguminous family. Leguminous plants have a unique ability to fix atmospheric nitrogen through a symbiotic relationship with certain bacteria.

3. **Know the Role of Bacteria**: The bacteria that are responsible for nitrogen fixation live in root nodules of leguminous plants. They convert atmospheric nitrogen (N₂) into a soluble form (like ammonia) that can be utilized by plants.

4. **Evaluate the Given Options**: The options provided include various crops. We need to identify which of these belongs to the leguminous family.
- **Pea Plant**: This is a leguminous crop and is known for its nitrogen-fixing ability.
- **Apple**: This is a fruit tree and does not fix nitrogen.
- **Paddy (Rice)**: This is a cereal crop and does not belong to the leguminous family.
- **Potato**: This is a tuber and also does not fix nitrogen.

5. **Select the Correct Answer**: Based on the evaluation, the pea plant is the only crop from the options that enriches the soil with nitrogen.

### Conclusion:
The crop that would enrich the soil with nitrogen is the **pea plant**.

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