Assertion: Leguminous plants are the best preferred for crop rotation.
Reason: They have root nodules which have nitrogen-fixing bacteria Clostridium.

Options

A. If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion
B. If both Assertion and Reason are true and the Reason is not the correct explanation of the Assertion.
C. If Assertion is true but the Reason is false.
D. If both Assertion and Reason are false.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that leguminous plants are the best preferred for crop rotation. This is true because leguminous plants, such as beans and peas, have unique properties that benefit soil health and fertility.

2. **Understanding the Reason**: The reason provided is that leguminous plants have root nodules which contain nitrogen-fixing bacteria. While the assertion is correct, the specific bacteria mentioned, Clostridium, is not the primary nitrogen-fixing bacteria associated with leguminous plants. Instead, the main nitrogen-fixing bacteria found in the root nodules of leguminous plants are from the genus Rhizobium.

3. **Linking Assertion and Reason**: The reason explains why leguminous plants are preferred for crop rotation. The presence of nitrogen-fixing bacteria in the root nodules allows these plants to convert atmospheric nitrogen into a form that can be used by plants, thus enhancing soil fertility.

4. **Conclusion**: Both the assertion and the reason are true. However, the reason does not correctly identify the nitrogen-fixing bacteria associated with leguminous plants. Therefore, while the assertion is supported by the reason, the specific details in the reason are inaccurate.

5. **Final Answer**: The assertion is true, but the reason is partially incorrect due to the misidentification of the bacteria. Therefore, the correct option would be that both statements are true, but the reason is not the correct explanation for the assertion.

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