Which is associated with pearl formation ?

Options

A. Pecten
B. Ostrea
C. Nautilus
D. Pinctada

Answer

To determine which organism is associated with pearl formation, we need to analyze the options provided and understand the biological context of pearl formation.

### Step-by-Step Solution:

1. **Understanding Pearl Formation**:
- Pearls are formed by certain mollusks as a defense mechanism against irritants, such as a parasite entering their shell or damage to their body. The mollusk secretes layers of nacre (mother of pearl) around the irritant, which eventually forms a pearl.

2. **Identifying the Options**:
- The options given are:
1. Pectin
2. Austria
3. Nautilus
4. Pink Tarda

3. **Analyzing Each Option**:
- **Option 1: Pectin**:
- This is a genus that includes scallops. Scallops are not primarily known for pearl formation.
- **Option 2: Austria**:
- This refers to the genus "Ostrea," which includes oysters. Oysters are well-known for producing pearls, particularly the edible varieties.
- **Option 3: Nautilus**:
- Nautilus is a cephalopod and does not produce pearls. It has an external shell but is not associated with pearl formation.
- **Option 4: Pink Tarda**:
- This is a genus known for its significant role in pearl formation. Specifically, "Pinctada" is the genus that includes species like Pinctada maxima, which is famous for producing large pearls.

4. **Conclusion**:
- Based on the analysis, the organism most associated with pearl formation is **Option 4: Pink Tarda** (correctly referred to as Pinctada).

### Final Answer:
The organism associated with pearl formation is **Pinctada (Pink Tarda)**.

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