Prolonged inhalation of _____ can lead to life-threatening diseases such as cancer.

Options

A. Carbon monoxide
B. Carbon dioxide
C. Lead
D. Sulphur dioxide

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about a substance that, when inhaled for a prolonged period, can lead to life-threatening diseases such as cancer.

2. **Identifying Potential Substances**: The question provides four options to choose from. We need to analyze each option to determine which one is linked to serious health issues like cancer.

3. **Analyzing Each Option**:
- **Option 1: Carbon Monoxide (CO)**: While carbon monoxide is harmful and can cause serious health issues, it is primarily known for causing suffocation and does not directly lead to cancer.
- **Option 2: Carbon Dioxide (CO2)**: Carbon dioxide is a natural component of the air we breathe and is not known to cause cancer.
- **Option 3: Lead**: Prolonged inhalation of lead can lead to severe health issues, including damage to the kidneys and nervous system, and it is associated with an increased risk of cancer.
- **Option 4: Sulfur Dioxide (SO2)**: Sulfur dioxide can cause respiratory problems but is not directly linked to cancer.

4. **Selecting the Correct Answer**: Based on the analysis, the substance that can lead to life-threatening diseases such as cancer when inhaled for a prolonged period is **Lead**.

5. **Final Answer**: Prolonged inhalation of **Lead** can lead to life-threatening diseases such as cancer.

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