A chemical carcinogen present in tobacco smoke is responsible for

Options

A. skin cancer
B. pancreatic cancer
C. stomach cancer
D. lung cancer.

Answer

### Step-by-Step Text Solution:

1. **Understanding Tobacco Smoke**: Tobacco smoke contains a complex mixture of chemicals, including approximately 70 known carcinogens. Carcinogens are substances that can lead to cancer.

2. **Identifying Key Carcinogens**: Among the various carcinogens present in tobacco smoke, acrolein is identified as the most prevalent one. Other notable carcinogens include nitrogen oxides, acetaldehyde, and formaldehyde.

3. **Mechanism of Action**: When tobacco smoke is inhaled, these carcinogens can directly or indirectly affect the pulmonary system. Acrolein, in particular, has a direct impact on the pulmonary cilia, which are tiny hair-like structures lining the lungs that help clear out mucus and debris.

4. **Effects on Health**: The presence of these carcinogens in tobacco smoke is primarily linked to lung cancer. While other types of cancer (such as skin, pancreatic, and stomach cancer) are serious health concerns, the specific carcinogens in tobacco smoke are most strongly associated with lung cancer.

5. **Conclusion**: Therefore, the correct answer to the question regarding which cancer is primarily caused by a chemical carcinogen present in tobacco smoke is lung cancer.

### Final Answer:
**Lung cancer is the disease caused by the inhalation of tobacco smoke and the carcinogens it contains.**

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