Fluorosis, a bone disease is caused by the presence of

Options

A. Pesticidies in water
B. Fluorides in water
C. Carbon monoxide in air
D. Photochemical

Answer

**Step-by-Step Solution:**

1. **Understanding Fluorosis**: Fluorosis is a bone disease that occurs due to the accumulation of fluorides in the body. It primarily affects the bones and teeth.

2. **Identifying the Cause**: The disease is specifically linked to the presence of excess fluorides in drinking water. This fluoride can come from natural sources or from human activities.

3. **Analyzing the Options**:
- **Option 1: Pesticides in water** - This is not related to fluorosis, as the name suggests that fluorosis is connected to fluorine.
- **Option 2: Fluorides in water** - This is directly related to the cause of fluorosis, as excessive fluoride intake leads to the disease.
- **Option 3: Carbon monoxide in air** - This is unrelated to fluorosis, as it is not a water-based issue.
- **Option 4: Photochemical** - This option is also incorrect, as it does not pertain to the cause of fluorosis.

4. **Conclusion**: After analyzing all options, the correct answer is that fluorosis is caused by the presence of fluorides in water.

**Final Answer**: Fluorosis, a bone disease, is caused by the presence of fluorides in water.

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