Given these blood vessels
1.Aorta
2. vena cava
3. Pulmonary arteries
4. Pulmonary veins
Which vessels carry oxygen -rich blood ?

Options

A. (a) 1,3
B. (b) 1,4
C. (c) 2,3
D. (d) 2,4

Answer

To determine which blood vessels carry oxygen-rich blood, we will analyze each of the given blood vessels one by one.

### Step-by-Step Solution:

1. **Identify the Aorta**:
- The aorta is the largest artery in the body. It carries blood away from the heart to the rest of the body.
- The blood in the aorta is oxygenated because it is pumped from the left ventricle of the heart, which receives oxygen-rich blood from the lungs.
- **Conclusion**: The aorta carries oxygen-rich blood.

2. **Identify the Vena Cava**:
- The vena cava consists of two large veins: the superior vena cava and the inferior vena cava.
- These veins carry deoxygenated blood from the body back to the heart, specifically to the right atrium.
- **Conclusion**: The vena cava carries deoxygenated blood.

3. **Identify the Pulmonary Arteries**:
- The pulmonary arteries carry blood from the right ventricle of the heart to the lungs.
- This blood is deoxygenated because it is being sent to the lungs to receive oxygen.
- **Conclusion**: The pulmonary arteries carry deoxygenated blood.

4. **Identify the Pulmonary Veins**:
- The pulmonary veins carry blood from the lungs back to the left atrium of the heart.
- This blood is oxygenated because it has just picked up oxygen in the lungs.
- **Conclusion**: The pulmonary veins carry oxygen-rich blood.

### Final Answer:
The blood vessels that carry oxygen-rich blood are the **Aorta (1)** and **Pulmonary Veins (4)**.