Assertion: Bone has very hard matrix whereas cartilage has pliable matrix.
Reason: Bone has calcium salts in its matrix whereas cartilage has chondroitin salts in its matrix.

Options

A. If both assertion and reason are ture and reason is the corect explanation of assertion
B. If both assertion and reason are ture but reson is not the correct explanation of assertion
C. If assertion is true reason is false
D. If both assertion and reason are false

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that "Bone has a very hard matrix whereas cartilage has a pliable matrix."
- This is true because bone is known for its rigidity and strength, while cartilage is more flexible and can bend without breaking.

2. **Understanding the Reason:**
- The reason provided is "Bone has calcium salts in its matrix whereas cartilage has chondroitin salts in its matrix."
- This statement is also true. The presence of calcium salts in the bone matrix contributes to its hardness, while chondroitin sulfate in cartilage gives it flexibility and pliability.

3. **Evaluating the Relationship:**
- The reason explains why the assertion is true. The hardness of bone is due to the calcium salts, and the pliability of cartilage is due to the chondroitin salts.
- Therefore, the reason is a correct explanation for the assertion.

4. **Conclusion:**
- Both the assertion and the reason are true, and the reason correctly explains the assertion.
- Hence, the correct answer is option A: "Both assertion and reason are true and the reason is the correct explanation for assertion."