Arteries normally carry oxygen rich blood whereas veins normally carry carbon dioxide rich blood.
Name one vein which carries oxygen rich blood.

Answer

### Step-by-Step Solution:

1. **Understanding Blood Vessels**: First, we need to understand the roles of arteries and veins in the circulatory system. Arteries typically carry oxygen-rich blood away from the heart to the body, while veins usually carry carbon dioxide-rich blood back to the heart.

2. **Identifying the Exception**: The question asks for a specific vein that carries oxygen-rich blood, which is an exception to the general rule that veins carry carbon dioxide-rich blood.

3. **Recognizing the Pulmonary Vein**: The pulmonary vein is the specific vein that carries oxygen-rich blood. It transports oxygenated blood from the lungs to the left atrium of the heart.

4. **Conclusion**: Therefore, the answer to the question is the **pulmonary vein**.

### Final Answer:
The vein that carries oxygen-rich blood is the **pulmonary vein**.

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