Tusks of Elephant are made of

Options

A. Ivory
B. Hard bone
C. Fortified cartilage
D. Mixture of calcium and silica .

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks what the tusks of elephants are made of. This requires knowledge of elephant anatomy and the composition of their tusks.

2. **Identifying the Options**: The options provided are:
- Ivory
- Hard bone
- Fortified cartilage
- Mixture of calcium and silica

3. **Analyzing the Options**:
- **Ivory**: This is a dense, hard white substance that is primarily made of dentine, which is a calcified tissue. It is known for its use in art and decoration and is the primary material of elephant tusks.
- **Hard bone**: While tusks are hard, they are not made of bone but rather of dentine, which is different from bone.
- **Fortified cartilage**: Cartilage is a flexible tissue and does not constitute tusks.
- **Mixture of calcium and silica**: While tusks do contain minerals, they are not primarily made of a mixture of calcium and silica.

4. **Conclusion**: Based on the analysis, the correct answer is that tusks of elephants are made of **ivory**.

5. **Final Answer**: The tusks of elephants are made of **ivory**.

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