Which of the following changes is not a result of an increase in water pollution?

Options

A. Increase in the cases of jaundice and cholera
B. Increase in the amount of rainfall and floods
C. Increase in the chemical content of water bodies
D. Increase in the biological activity in water bodies

Answer

To determine which of the following changes is not a result of an increase in water pollution, we need to analyze each option provided in the context of water pollution's effects.

### Step-by-Step Solution:

1. **Identify the Options**: The options given are:
- A) Increase in the cases of joint disease and cholera
- B) Increase in the amount of rainfall and floods
- C) Increase in the chemical content of water bodies
- D) Increase in the biological activities in water bodies

2. **Analyze Each Option**:
- **Option A**: Increase in the cases of joint disease and cholera.
- Water pollution can lead to contaminated water sources, which can cause diseases like cholera and other waterborne diseases. Thus, this option is a result of water pollution.

- **Option B**: Increase in the amount of rainfall and floods.
- Rainfall and floods are primarily influenced by climate change and weather patterns, not directly by water pollution. Therefore, this option is likely not a result of water pollution.

- **Option C**: Increase in the chemical content of water bodies.
- Water pollution often involves the introduction of chemicals into water bodies, leading to an increase in their chemical content. Hence, this option is a direct result of water pollution.

- **Option D**: Increase in the biological activities in water bodies.
- Water pollution can lead to an increase in certain biological activities, such as the growth of harmful algal blooms due to nutrient pollution. Thus, this option is also a result of water pollution.

3. **Conclusion**: Based on the analysis, the change that is not a result of an increase in water pollution is **Option B: Increase in the amount of rainfall and floods**.

### Final Answer:
**B) Increase in the amount of rainfall and floods**

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