Which of the following statements is incorrect?

Options

A. Discharge of domestic sewage into water bodies makes water unfit for bathing
B. Discharge of treated industrial waste into water bodies makes water fit for bathing
C. Discharge of pesticides into water bodies makes water rich in nutrients and fit for drinking
D. Discharge of mercury into water bodies makes it unfit for drinking

Answer

To determine which statement is incorrect regarding the pollution of water bodies, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement 1: Discharge of domestic sewage into water bodies makes water unfit for bathing.**
- **Analysis:** Domestic sewage contains various contaminants and pathogens that can harm human health. Therefore, this statement is correct as it accurately describes the impact of sewage on water quality.

2. **Statement 2: Discharge of treated industrial waste into water bodies makes water fit for bathing.**
- **Analysis:** Treated industrial waste may still contain some impurities, but if the treatment process is effective, it can make the water relatively safer for bathing. However, this statement can be misleading, as the safety of the water depends on the extent of treatment. For the purpose of this question, we can consider this statement as generally correct.

3. **Statement 3: Discharge of pesticides into water bodies makes water rich in nutrients and fit for drinking.**
- **Analysis:** Pesticides are toxic chemicals that can contaminate water bodies. They do not enrich the water with nutrients; rather, they introduce harmful substances that make the water unsafe for drinking. This statement is incorrect.

4. **Statement 4: Discharge of mercury into water bodies makes it unfit for drinking.**
- **Analysis:** Mercury is a highly toxic heavy metal that poses serious health risks. Its presence in water makes it unfit for drinking. Thus, this statement is correct.

### Conclusion:
The incorrect statement among the options provided is **Statement 3**: "Discharge of pesticides into water bodies makes water rich in nutrients and fit for drinking."

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