Which animal swims by jet propulsion mechanism :-

Options

A. Cypraea
B. Pinctada
C. Unio
D. Cuttle fish

Answer

**Step-by-Step Solution:**

1. **Understanding Jet Propulsion**: Jet propulsion is a method of movement used by certain animals where they expel water from their bodies to propel themselves forward. This mechanism is commonly seen in cephalopods.

2. **Analyzing the Options**:
- **Option 1: Sepria** - This is a type of small sea snake, which does not use jet propulsion for swimming. Therefore, this option is incorrect.
- **Option 2: Pink Tadda** - This refers to a genus of saltwater oysters. Oysters are sessile and do not swim using jet propulsion. Hence, this option is also incorrect.
- **Option 3: Uneo** - These are freshwater mussels. Similar to oysters, they do not swim using jet propulsion, making this option incorrect as well.
- **Option 4: Cuttlefish** - Cuttlefish are known for their ability to swim using jet propulsion. They can fill their mantle cavity with water and expel it to move quickly, making this option the correct answer.

3. **Conclusion**: After analyzing all the options, the animal that swims by the jet propulsion mechanism is the cuttlefish.

**Final Answer**: The animal that swims by jet propulsion mechanism is the **cuttlefish**.

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