Respiration is the physilogical process in which

Options

A. (1) breathing occur
B. (2) breathing , external respiration occurs
C. (3) only inspiration occurs
D. (4) breathing , external respiration and cellular respiration occurs

Answer

**Step-by-Step Solution:**

1. **Understanding Respiration**: Respiration is a physiological process that involves the exchange of gases and the biochemical processes that occur within cells.

2. **Identifying the Components of Respiration**:
- **Breathing**: This is the physical act of inhaling and exhaling air, which is essential for gas exchange.
- **External Respiration**: This refers to the exchange of gases (oxygen and carbon dioxide) between the atmosphere and the blood in the lungs.
- **Cellular Respiration**: This is the biochemical process that occurs within cells, where glucose is oxidized to produce energy, carbon dioxide, and water.

3. **Connecting the Components**: All three components (breathing, external respiration, and cellular respiration) are interconnected and essential for the overall process of respiration.

4. **Conclusion**: Therefore, respiration is the physiological process in which breathing, external respiration, and cellular respiration occurs.

5. **Final Answer**: The correct option is the fourth one: "breathing, external respiration, and cellular respiration occurs."

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