Smoke of tobacoo usually contains
A. carbon monooxide
B. nicotine
C. tar

Options

A. A,B
B. A,C
C. B,C
D. A,B,C

Answer

To answer the question regarding the components found in tobacco smoke, we can break down the options provided:

1. **Understanding the Components**:
- Tobacco smoke is known to contain various harmful substances. The question lists three options: carbon monoxide, nicotine, and tar.

2. **Analyzing Each Option**:
- **A. Carbon Monoxide**: This is a colorless, odorless gas that is produced when tobacco is burned. It is harmful as it can interfere with the blood's ability to carry oxygen.
- **B. Nicotine**: This is an alkaloid found in tobacco plants. It is a stimulant and is responsible for the addictive properties of tobacco.
- **C. Tar**: This is a sticky substance that is produced when tobacco is burned. It contains many harmful chemicals and is responsible for many of the respiratory issues associated with smoking.

3. **Conclusion**:
- Since all three options (carbon monoxide, nicotine, and tar) are known to be present in tobacco smoke, the correct answer to the question is that tobacco smoke usually contains **A. carbon monoxide, B. nicotine, and C. tar**.

### Final Answer:
Tobacco smoke usually contains A. carbon monoxide, B. nicotine, and C. tar.

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