Liver cancer is caused by

Options

A. Aflatoxin
B. N-nitraso dimethylene
C. Cadmium oxide
D. Mustard gas

Answer

### Step-by-Step Solution:

1. **Understanding Liver Cancer**: Liver cancer is a type of cancer that originates in the liver. It can be caused by various factors, including exposure to certain toxins.

2. **Identifying Potential Causes**: The question provides four options that may be linked to liver cancer:
- Aflatoxin
- N-nitros dimethylamine
- Cadmium oxide
- Mustard gas

3. **Analyzing Aflatoxin**:
- Aflatoxin is a toxic compound produced by certain molds (fungi) that grow on agricultural crops, particularly when they are stored improperly.
- High levels of aflatoxin exposure can lead to liver damage and are classified as a carcinogen, meaning they can cause cancer.

4. **Examining Other Options**:
- **N-nitros dimethylamine**: While it can damage the liver, it is also known to affect other organs like the kidneys and lungs, leading to conditions such as jaundice and vomiting.
- **Cadmium oxide**: This compound primarily causes respiratory issues and acute toxic pneumonitis, not specifically liver cancer.
- **Mustard gas**: This is known for its severe effects on the respiratory system and does not directly cause liver cancer.

5. **Conclusion**: Based on the analysis, aflatoxin is the most directly linked to causing liver cancer due to its carcinogenic properties and its association with liver damage.

### Final Answer:
Liver cancer is caused by **Aflatoxin**.

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