Assertion: Spongy bones are specialised to form erythrocytes.
Reason: They contain osteocytes and osteoblasts.

Options

A. If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
B. If both Assertion and Reason are true, but Reason is not the correct explanation of Assertion.
C. If Assertion is true, but Reason is false.
D. Both Assertion and Reason are false.

Answer

To analyze the given assertion and reason, let's break it down step by step.

### Step 1: Understand the Assertion
The assertion states that "Spongy bones are specialized to form erythrocytes."
- Spongy bone, also known as cancellous bone, is a type of bone tissue that is lighter and less dense than compact bone.
- It is found at the ends of long bones and in the interiors of others.
- One of the key functions of spongy bone is to house red bone marrow, which is responsible for the production of erythrocytes (red blood cells).

### Step 2: Understand the Reason
The reason states that "They contain osteocytes and osteoblasts."
- Osteocytes are mature bone cells that maintain bone tissue, while osteoblasts are cells that are responsible for bone formation.
- While these cells are important for the maintenance and formation of bone, they are not directly involved in the formation of erythrocytes.

### Step 3: Evaluate the Relationship
Now we need to evaluate the relationship between the assertion and the reason:
- The assertion is true because spongy bone does play a role in the formation of erythrocytes due to the presence of red bone marrow.
- The reason is partially true as spongy bone contains osteocytes and osteoblasts, but these cells do not directly contribute to the formation of erythrocytes.

### Conclusion
- Therefore, the assertion is true, but the reason does not adequately support the assertion because the presence of osteocytes and osteoblasts does not directly relate to the formation of erythrocytes.

### Final Answer
- The assertion is true, but the reason is not a valid explanation for the assertion.

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