The green revolution succeeded in increasing the yield of crops mainly due to the use of
I) improved varieties of the crops
II) agro-chemicals
III) better management practices
Choose the correct option.

Options

A. I and II
B. I and III
C. II and III
D. I, II and III

Answer

To solve the question regarding the success of the Green Revolution in increasing crop yields, we will analyze each of the given options step by step.

### Step-by-Step Solution:

1. **Understanding the Green Revolution**:
The Green Revolution refers to a period in agricultural history characterized by the adoption of modern agricultural techniques and technologies aimed at increasing food production. This involved the introduction of high-yielding varieties (HYVs) of crops, the use of agrochemicals, and improved management practices.

2. **Evaluating Option I - Improved Varieties of Crops**:
- The introduction of high-yielding varieties of crops was a fundamental aspect of the Green Revolution. These varieties were specifically bred to produce more grain per plant and were more resilient to diseases and pests.
- **Conclusion**: This option is correct.

3. **Evaluating Option II - Agro-Chemicals**:
- The use of agrochemicals, including fertilizers and pesticides, played a crucial role in enhancing crop yields. Fertilizers improved soil fertility, while pesticides helped protect crops from pests and diseases.
- **Conclusion**: This option is also correct.

4. **Evaluating Option III - Better Management Practices**:
- Better management practices included improved irrigation techniques, the use of machinery (like tractors), and advanced farming methods. These practices contributed significantly to the efficiency and productivity of farming.
- **Conclusion**: This option is correct as well.

5. **Final Conclusion**:
- All three factors—improved varieties of crops, agro-chemicals, and better management practices—contributed to the success of the Green Revolution in increasing crop yields. Therefore, the correct answer is that all three options are correct.

### Correct Option:
- **Option D**: All of the above (I, II, and III).

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