Which of the following is mismatched?

Options

A. Torpedo : Electric organs, modified muscles supplied with nerves
B. Trygon :Dorsal fin is modifield into a poison sting
C. Exocoetus : Pectoral fin becomes large by which it can leap into air
D. Hippocampus : Female bears a brood pouch

Answer

To determine which of the given options is mismatched, we will analyze each option one by one.

### Step-by-Step Solution:

1. **Identify the First Option: Torpedo**
- **Feature:** It has electric organs, modified muscles supplied with nerves.
- **Analysis:** Torpedo is a type of electric ray belonging to the class Chondrichthyes (cartilaginous fish). It is known for having electric organs that can produce electric shocks. The description is accurate.
- **Conclusion:** This is a correct match.

2. **Identify the Second Option: Trigon**
- **Feature:** Dorsal fin is modified into a poison sting.
- **Analysis:** Trigon refers to the stingray, which indeed has a dorsal fin modified into a venomous spine or sting. This is a characteristic feature of stingrays.
- **Conclusion:** This is a correct match.

3. **Identify the Third Option: Exocoitus**
- **Feature:** Pectoral fin becomes large by which it can leap into air.
- **Analysis:** Exocoitus is commonly known as the flying fish. It is well-known for its ability to leap out of the water and glide through the air using its enlarged pectoral fins.
- **Conclusion:** This is a correct match.

4. **Identify the Fourth Option: Hippocampus**
- **Feature:** Female bears a brood pouch.
- **Analysis:** Hippocampus refers to seahorses. In seahorses, it is the male that has a brood pouch where it carries the fertilized eggs until they hatch. The feature described is incorrect as it states that the female bears the brood pouch.
- **Conclusion:** This is a mismatched statement.

### Final Answer:
The mismatched option is **D: Hippocampus - Female bears a brood pouch.**

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