Which one is a fish ?

Options

A. Sea Horse
B. Sea Cow
C. Sea Cucumber
D. Sea Urchin

Answer

To determine which one of the given options is a fish, we can analyze each option based on their biological classification.

### Step-by-Step Solution:

1. **Identify the Options**: We have four options to consider:
- A) Seahorse
- B) Sea Cow
- C) Sea Cucumber
- D) Sea Urchin

2. **Analyze Option A - Seahorse**:
- The seahorse, scientifically known as Hippocampus, is classified under the class Osteichthyes, which are bony fishes.
- Seahorses are indeed fish and are known for their unique reproductive behavior, where males carry the young.

3. **Analyze Option B - Sea Cow**:
- The sea cow, or manatee, is scientifically known as Hydrodamalis.
- Sea cows are large aquatic mammals belonging to the class Mammalia, which means they are not fish.

4. **Analyze Option C - Sea Cucumber**:
- The sea cucumber, scientifically known as Holothuria, is a marine animal that belongs to the phylum Echinodermata.
- Echinoderms are not classified as fish.

5. **Analyze Option D - Sea Urchin**:
- The sea urchin is also an echinoderm and does not belong to the fish classification.

6. **Conclusion**:
- After analyzing all options, the only option that is classified as a fish is **Option A - Seahorse**.

### Final Answer:
The correct answer is **A) Seahorse**.

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