Black-foot disease is caused due to groundwater contaminated with excess of

Options

A. nitrate
B. fluoride
C. arsenie
D. sulphur

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks about the cause of black-foot disease, specifically which contaminant in groundwater is responsible for it.

2. **Identifying the Options:**
The options provided are:
- A) Nitrate
- B) Fluoride
- C) Arsenic
- D) Sulphur

3. **Researching Black-foot Disease:**
Black-foot disease is known to be associated with exposure to certain contaminants in drinking water. It primarily affects the blood vessels and can lead to severe complications such as gangrene.

4. **Identifying the Contaminant:**
Research indicates that black-foot disease is linked to arsenic contamination in groundwater. It has been notably observed in certain regions, particularly in Taiwan, China, where arsenic levels in drinking water are high.

5. **Understanding the Effects of Arsenic:**
Arsenic is a toxic element that can lead to various health issues, including skin lesions, cancer (in organs such as skin, lungs, bladder, and kidneys), and other serious health problems.

6. **Conclusion:**
Based on the information gathered, the correct answer to the question is that black-foot disease is caused by groundwater contaminated with excess **arsenic**.

**Final Answer:**
Black-foot disease is caused due to groundwater contaminated with excess **arsenic** (Option C).

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