The pearls are formed of

Options

A. Calcium phsophate
B. Calcium carbonate
C. Magnesium trisilicate
D. Calcium sulfate

Answer

**Step-by-Step Solution:**

1. **Understanding Pearls**: Pearls are hard, glistening objects that are formed within the soft tissues of certain mollusks, particularly in the mantle.

2. **Identifying the Composition**: The primary component of pearls is essential to answer the question. Pearls are known to be made up of a specific substance.

3. **Reviewing Options**: The options given are:
- a. Calcium phosphate
- b. Calcium carbonate
- c. Magnesium trisilicate
- d. Calcium sulphate

4. **Researching the Correct Composition**: Pearls are primarily composed of calcium carbonate, which is produced in a crystalline form. This is a well-established fact in biology.

5. **Conclusion**: Based on the information gathered, the correct answer to the question "The pearls are formed of" is **b. Calcium carbonate**.

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