Which bone during its development is not a cartilage

Options

A. Malleus
B. Humerus
C. Incus
D. Nasal

Explanation

**Step-by-Step Solution:**

1. **Understanding Bone Development**: Most bones in the human body develop from a cartilage model through a process called endochondral ossification. However, some bones develop directly from mesenchymal tissue without a cartilage stage.

2. **Identifying the Options**: The question provides several options: malleus, incus, humerus, and nasal bone. We need to determine which of these bones does not develop from cartilage.

3. **Analyzing Each Option**:
- **Malleus and Incus**: These are two of the three ossicles in the middle ear. They are classified as membranous bones, meaning they do not develop from a cartilage model.
- **Humerus**: This is a long bone of the arm that develops from a cartilage model through endochondral ossification.
- **Nasal Bone**: The nasal bones are also classified as membranous bones and do not develop from cartilage.

4. **Conclusion**: Among the options, the nasal bone is specifically noted for its development without a cartilage stage. Therefore, the answer to the question is the nasal bone.

5. **Final Answer**: The bone that is not a cartilage during its development is the **nasal bone** (Option D).

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