Breathing :

Options

A. ventilates lungs
B. draws air into airways
C. expels air from airways
D. all of the above

Answer

**Step-by-Step Solution:**

1. **Understanding Breathing**: Breathing is a vital process related to the respiratory system, primarily responsible for the exchange of gases in our body. It involves taking in oxygen and expelling carbon dioxide.

2. **Significance of Breathing**: The main function of breathing is to supply oxygen to body tissues and remove carbon dioxide produced during metabolism. This process is crucial for maintaining cellular functions.

3. **Process of Breathing**: Breathing consists of two main phases:
- **Inspiration**: This is the process of inhaling air into the lungs, allowing oxygen to enter the alveoli (air sacs) for gas exchange.
- **Expiration**: This is the process of exhaling air out of the lungs, which removes carbon dioxide from the body.

4. **Movement of Air**: The act of breathing ensures that air is moved in and out of the lungs, facilitating the necessary gas exchange. This movement is also referred to as pulmonary ventilation.

5. **Evaluating Options**:
- **Option A**: "It ventilates the lungs." This is correct as breathing involves moving air in and out of the lungs.
- **Option B**: "It draws air into the airways." This is also correct since inspiration draws air into the lungs.
- **Option C**: "It expels the air." This is correct as well, referring to the process of expiration.
- **Option D**: "All of the above." Since all previous statements are correct, this option is the best choice.

6. **Conclusion**: The correct answer to the question regarding breathing is **Option D: All of the above**.

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