Choose the correct statement that describes arteries.

Options

A. They have thick elastic walls, blood flows under high pressure , collect blood from different organs and bring it back to the heart
B. They have thin walls with valves inside, blood flows under low pressure and carry blood away from the heart to various organs of the body
C. They have thick elastic walls,blood flows under low pressure carry blood from the heart to various of the body
D. They have thick elastic walls without valves inside , blood flows under high pressure and carry blood away from the heart to different parts of the body .

Explanation

**Step-by-Step Solution:**

1. **Understanding Arteries**:
- Arteries are blood vessels that carry blood away from the heart to various parts of the body.

2. **Function of Arteries**:
- The primary function of arteries is to transport oxygenated blood (with the exception of pulmonary arteries) from the heart to all body parts.

3. **Blood Pressure in Arteries**:
- Blood flows through arteries under high pressure. This is necessary to ensure that blood reaches all parts of the body efficiently.

4. **Structure of Arteries**:
- Due to the high pressure of the blood, arteries have thick and elastic walls. This structural feature helps them withstand the pressure and prevents them from bursting.

5. **Evaluating Statements**:
- Now, we need to evaluate the given statements about arteries:
- **Statement 1**: "They have thick elastic walls." - This is correct.
- **Statement 2**: "Blood flows under high pressure." - This is also correct.
- **Statement 3**: "Collect blood from different organs and bring it back to heart." - This is incorrect; this describes veins, not arteries.
- **Statement 4**: "They have thin walls." - This is incorrect; arteries have thick walls.
- **Statement 5**: "They have thick elastic walls, blood flows under low pressure, and carry blood away from the heart to different parts of the body." - This is incorrect because blood does not flow under low pressure in arteries.

6. **Identifying the Correct Statement**:
- The correct statement that describes arteries is: "They have thick elastic walls, blood flows under high pressure, and carry blood away from the heart to different parts of the body."

7. **Conclusion**:
- Therefore, the correct answer is option D.

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