Knock Knee' syndrome occurs due to the pollution of :

Options

A. Heavy metals
B. Fluorides
C. Nitrates
D. Phosphates

Answer

### Step-by-Step Solution:

1. **Understanding Knock Knee Syndrome**:
- Knock knee syndrome, also known as genu valgum, is a condition where the knees angle inwards and touch each other when the legs are straightened. This condition can affect mobility and posture.

2. **Identifying Causes of Knock Knee Syndrome**:
- The condition can be caused by various factors, including nutritional deficiencies, genetic factors, and environmental influences. One significant environmental factor is pollution.

3. **Analyzing the Options Provided**:
- The options given are heavy metals, fluorides, nitrates, and phosphates. We need to determine which of these pollutants is directly linked to knock knee syndrome.

4. **Researching the Effects of Each Pollutant**:
- **Heavy Metals**: These can cause various health issues but are not specifically linked to knock knee syndrome.
- **Fluorides**: Excessive fluoride intake, particularly from contaminated water, can lead to several health problems, including neuromuscular disorders and skeletal deformities, which can manifest as knock knee syndrome.
- **Nitrates**: High levels of nitrates in water can lead to methhemoglobinemia but are not associated with knock knee syndrome.
- **Phosphates**: These are primarily linked to kidney diseases and are not directly related to knock knee syndrome.

5. **Conclusion**:
- Based on the analysis, fluorides are the pollutant that is most closely associated with knock knee syndrome due to their impact on bone and joint health.

### Final Answer:
Knock Knee syndrome occurs due to the pollution of **fluorides**.

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