Elongation of bone occurs due to  

Options

A. Spongy bone
B. hyaline cartilage of diaphysis
C. hyaline cartilage of epiphysis
D. All the above

Answer

**Step-by-Step Solution:**

1. **Understanding Bone Structure**:
- Bones are made up of different types of tissues, including spongy bone, compact bone, and cartilage. The structure of a long bone includes the diaphysis (the shaft) and epiphysis (the ends).

2. **Identifying the Role of Diaphysis**:
- The diaphysis is the main or central part of a long bone. It is primarily composed of compact bone and does not contribute to the elongation of the bone.

3. **Evaluating Spongy Bone**:
- Spongy bone, found mainly at the ends of bones and within the epiphysis, provides structural support but does not play a direct role in the elongation of the bone.

4. **Focusing on Hyaline Cartilage**:
- The hyaline cartilage is present at the epiphysis of long bones. This cartilage is crucial for bone growth and elongation, especially during the growth phase in children and adolescents.

5. **Conclusion**:
- The elongation of bone occurs specifically due to the hyaline cartilage of the epiphysis, as it allows for the growth and extension of the bone length. Therefore, the correct answer is "hyaline cartilage of the epiphysis".

**Final Answer**: Elongation of bone occurs due to the hyaline cartilage of the epiphysis.

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