Mode of controlling pollution in large cities include

Options

A. lessening the use of insecticides
B. proper disposal of organic wastes, sewage and industrial effluents
C. shifting of factories out of the residential area
D. all of these.

Answer

**Step-by-Step Solution:**

1. **Understanding Pollution Control**: Pollution in large cities can arise from various sources, including industrial activities, waste disposal, and agricultural practices. To effectively control pollution, we need to consider multiple strategies.

2. **Analyzing Option A - Lessening the Use of Insecticides**: Insecticides are chemicals used to eliminate pests that harm crops. However, their excessive use can lead to soil and water pollution. Reducing insecticide use can help minimize chemical runoff into water bodies, thus controlling pollution.

3. **Analyzing Option B - Proper Disposal of Organic Waste, Sewage, and Industrial Effluents**: Proper waste management is crucial. If organic waste, sewage, and industrial effluents are not treated before disposal, they can contaminate water sources and harm aquatic life. Therefore, proper treatment and disposal are essential for pollution control.

4. **Analyzing Option C - Shifting Factories Out of Residential Areas**: Factories often emit pollutants that can affect nearby residential areas. By relocating factories away from homes, we can reduce air and water pollution in residential zones. This helps protect the health of residents and the environment.

5. **Conclusion - Choosing the Correct Option**: All three options (A, B, and C) contribute to controlling pollution in large cities. Therefore, the correct answer is **D - All of these**.

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