Water pollution is due to

Options

A. Sulphur dioxide
B. Carbon dioxide
C. oxygen
D. Industrial discharges.

Answer

### Step-by-Step Solution:

1. **Understanding Water Pollution**: Water pollution refers to the contamination of water bodies (like rivers, lakes, oceans, and groundwater) due to harmful substances.

2. **Analyzing the Options**:
- **Option A: Sulfur Dioxide**: This gas is primarily known for causing air pollution and acid rain. While it can indirectly affect water bodies, it does not directly cause water pollution. Therefore, this option is incorrect.

- **Option B: Carbon Dioxide**: Although carbon dioxide is a greenhouse gas and contributes to air pollution, it is not a direct pollutant of water. In aquatic environments, a deficiency of carbon dioxide can affect the respiration of aquatic plants, but it does not cause water pollution itself. Thus, this option is also incorrect.

- **Option C: Oxygen**: Oxygen is essential for the survival of aquatic life. It is not a pollutant; rather, it is necessary for the health of aquatic ecosystems. Therefore, this option is incorrect as well.

- **Option D: Industrial Discharge**: Industrial discharge refers to the release of waste products from factories into water bodies. This can include a variety of harmful substances, including chemicals and heavy metals, which can severely contaminate water and harm aquatic life. This is a direct cause of water pollution.

3. **Conclusion**: Based on the analysis of the options, the correct answer is **Option D: Industrial Discharge**, as it is a significant contributor to water pollution.