"Itai-Itai" ("ouch-ouch") disease is caused by the poisoning of:

Options

A. Hg
B. Pb
C. As
D. Cd.

Answer

**Step-by-Step Solution:**

1. **Identify the Disease**: The question refers to "Itai-Itai" disease, which is also known as "ouch-ouch" disease.

2. **Determine the Cause**: Research indicates that Itai-Itai disease is primarily caused by the poisoning of cadmium.

3. **Understand the Mechanism**: Cadmium poisoning occurs due to long-term exposure, particularly through oral ingestion. This chronic exposure leads to various health issues, including Itai-Itai disease.

4. **Geographical Context**: Itai-Itai disease was notably prevalent in Japan, particularly in areas where cadmium contamination was significant, often due to industrial activities.

5. **Differentiate from Other Poisons**:
- Mercury exposure leads to Minamata disease.
- Lead exposure results in lead poisoning, affecting workers in industries dealing with lead.
- Arsenic exposure causes arsenic poisoning, which can occur through inhalation or ingestion.

6. **Conclusion**: The correct answer to the question is that Itai-Itai disease is caused by cadmium poisoning.

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