Which is more important for water pollution-

Options

A. Sound
B. `SO_(2)`
C. Salts of arsenic
D. Sewage

Answer

**Step-by-Step Solution:**

1. **Understanding Water Pollution**: Water pollution refers to the contamination of water bodies (like rivers, lakes, oceans) due to harmful substances. It can have severe effects on aquatic life and human health.

2. **Identifying the Options**: The question provides four options:
- A) Some (unspecified)
- B) Sulfur dioxide
- C) Salt of arsenic
- D) Sewage

3. **Analyzing Each Option**:
- **Some (unspecified)**: This option is vague and does not provide a clear substance or source of pollution.
- **Sulfur Dioxide**: While sulfur dioxide can contribute to air pollution and acid rain, its direct impact on water pollution is less significant compared to other options.
- **Salt of Arsenic**: Arsenic is toxic and can contaminate water, but it is not as prevalent as sewage in terms of volume and frequency of pollution.
- **Sewage**: This is wastewater that comes from households, including toilets, kitchens, and laundries. It contains various organic and inorganic materials, including debris, chemicals, and pathogens.

4. **Conclusion**: Among the options provided, sewage is the most significant contributor to water pollution. It is often discharged into water bodies without proper treatment, leading to serious health risks and ecological disturbances.

5. **Final Answer**: The most important factor for water pollution is **Sewage**.

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