Minamata disease is caused by mixing of ............ material in water.

Options

A. cadmium
B. mercury
C. iron
D. sodium

Explanation

**Step-by-Step Solution:**

1. **Understanding Minamata Disease**: Minamata disease is a neurological syndrome caused by severe mercury poisoning. It is important to identify the substance responsible for this disease.

2. **Identifying the Options**: The question provides four options:
- Cadmium
- Mercury
- Iron
- Sodium

3. **Researching Each Option**:
- **Cadmium**: While it is a toxic metal, it is not associated with Minamata disease.
- **Mercury**: This is a well-known neurotoxin and is directly linked to Minamata disease.
- **Iron**: Generally not toxic in normal amounts and does not cause Minamata disease.
- **Sodium**: An essential element for life, but not related to Minamata disease.

4. **Conclusion**: Based on the information, the correct answer is mercury, which is the substance that causes Minamata disease.

5. **Final Answer**: Minamata disease is caused by mixing of **mercury** material in water.

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