Sewage water is mostly constitutes

Options

A. Microoganisms
B. Light
C. Fishes
D. Aquatic plants

Explanation

To answer the question "Sewage water is mostly constituted of," we can break down the solution step by step.

### Step-by-Step Solution:

1. **Understanding Sewage Water Composition**:
- Sewage water is a mixture that primarily consists of water and various contaminants, including organic and inorganic materials.

2. **Identifying Key Components**:
- The main components of sewage water include microorganisms, nutrients (like nitrogen and phosphorus), organic matter, and inorganic substances.

3. **Role of Microorganisms**:
- Microorganisms play a crucial role in sewage treatment. They help in breaking down organic matter and removing pollutants through biological processes.

4. **Comparative Analysis**:
- While sewage water may contain fish and aquatic plants, the concentration of microorganisms is significantly higher. For instance, there can be about 100,000 microorganisms for every 10 to 100 aquatic plants.

5. **Conclusion**:
- Given the information, the primary constituents of sewage water are microorganisms. Therefore, the correct answer to the question is that sewage water is mostly constituted of microorganisms.

### Final Answer:
Sewage water is mostly constituted of microorganisms.

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