Which of the following is waste water?

Options

A. Water trickling from a damaged tap.
B. Water coming out of a shower
C. Water flowing in a river.
D. Water coming out of a laundry.

Explanation

### Step-by-Step Solution:

1. **Understanding Wastewater**: Wastewater refers to any water that has been used and contains waste products. This includes water from various sources such as homes, industries, and public facilities.

2. **Identifying the Options**: The question provides four options:
- Option A: Water trickling from a damaged tap
- Option B: Water coming from a shower
- Option C: Water flowing in a river
- Option D: Water coming out of a donkey

3. **Analyzing Each Option**:
- **Option A**: Water trickling from a damaged tap is considered wastewater because it is leaking and not being used properly.
- **Option B**: Water coming from a shower is also wastewater since it is used water that contains soap and other residues.
- **Option C**: Water flowing in a river is not wastewater. It is typically considered clean or pure water, unless contaminated by external sources.
- **Option D**: Water coming out of a donkey (referring to urine) is also considered wastewater as it contains waste products.

4. **Conclusion**: Based on the analysis, the only option that is not wastewater is **Option C: Water flowing in a river**.

### Final Answer:
**Option C: Water flowing in a river** is not wastewater.

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