The following are the symptoms of flourosis

Options

A. Knock-knee syndrome
B. Mottling of teeth
C. Hardening of the joints
D. all the above

Answer

**Step-by-Step Solution:**

1. **Understanding Fluorosis**: Fluorosis is a condition caused by excessive intake of fluoride, primarily through drinking water, food, or dental products. It primarily affects the teeth and bones.

2. **Identifying Symptoms**: The question asks for the symptoms of fluorosis. The common symptoms associated with fluorosis include:
- White spots on teeth
- Black spots on teeth
- Mottled (or mottling) teeth
- Pitted teeth

3. **Analyzing the Options**: The options provided are:
- Need
- Knock knee syndrome
- Mottling of teeth
- Hardening of joints
- All of the above

4. **Evaluating Each Option**:
- **Need**: This option does not relate to fluorosis.
- **Knock knee syndrome**: This is a condition where the knees bend inward and is not a symptom of fluorosis.
- **Mottling of teeth**: This is a direct symptom of fluorosis.
- **Hardening of joints**: This is also not a symptom of fluorosis.

5. **Conclusion**: The only symptom that is directly related to fluorosis from the options given is "mottling of teeth". Therefore, the correct answer is "Mottling of teeth".

**Final Answer**: Mottling of teeth is a symptom of fluorosis.

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