Step 1: Understanding the Concept:
Environmental sustainability in agriculture involves minimizing pollution, protecting soil resources, and conserving ecosystems while producing food.
Step 2: Detailed Explanation:
- Assertion (A) is correct: Organic farming is designed to promote environmental sustainability by working within natural ecological cycles.
- Reason (R) is correct: By avoiding synthetic inputs, organic farming reduces chemical runoff into water bodies, lowers greenhouse gas emissions, and preserves soil biodiversity.
- Relationship: Because the practices listed in (R) directly reduce environmental pollution and protect resources, they explain the mechanism behind the sustainability benefits described in (A). Therefore, (R) is the correct explanation of (A).
Step 3: Final Answer:
The correct option is (A).