Blood vessel carrying least `CO_(2)` is

Options

A. Pulmonary vein
B. Pulmonary artery
C. Vena cava
D. Hepatic vein

Answer

To solve the question of which blood vessel carries the least amount of carbon dioxide (CO2), we can follow these steps:

### Step-by-Step Solution:

1. **Understand Blood Composition**: Blood can be classified as oxygenated or deoxygenated based on its gas content. Oxygenated blood has a higher concentration of oxygen and a lower concentration of carbon dioxide, while deoxygenated blood has a higher concentration of carbon dioxide.

2. **Identify the Blood Vessels**: The question involves identifying different blood vessels:
- Pulmonary artery
- Vena cava
- Hepatic vein
- Pulmonary vein

3. **Analyze Each Vessel**:
- **Pulmonary Artery**: Carries deoxygenated blood from the heart to the lungs. This blood has a high concentration of CO2.
- **Vena Cava**: Returns deoxygenated blood from the body to the heart. This blood also has a high concentration of CO2.
- **Hepatic Vein**: Carries deoxygenated blood from the liver back to the heart. This blood also contains a significant amount of CO2.
- **Pulmonary Vein**: Carries oxygenated blood from the lungs back to the heart. This blood has a high concentration of oxygen and a low concentration of CO2.

4. **Conclusion**: Among the listed blood vessels, the pulmonary vein carries the least amount of CO2 because it transports oxygenated blood, which has a lower concentration of CO2 compared to deoxygenated blood in the other vessels.

5. **Final Answer**: Therefore, the blood vessel carrying the least CO2 is the **pulmonary vein**.