Hippocampus (Sea Horse) belong to the class

Options

A. Agnatha
B. Chondrichthyes
C. Osteichthyes
D. Mammals

Answer

To determine the class to which the Hippocampus (Sea Horse) belongs, we can follow these steps:

### Step 1: Identify the options provided.
The options given are:
- Egnatha
- Chondrichthys
- Osteichthys
- Mammals

### Step 2: Understand the classification of these groups.
1. **Egnatha**: This is a superclass that includes jawless fishes, such as lampreys and hagfish.
2. **Chondrichthys**: This class includes cartilaginous fishes, such as sharks and rays. They have a skeleton made of cartilage rather than bone.
3. **Osteichthys**: This class includes bony fishes. It encompasses a wide variety of fish, including ray-finned and lobe-finned fishes.
4. **Mammals**: This class consists of warm-blooded animals that have mammary glands, which produce milk.

### Step 3: Determine the correct class for Hippocampus.
The Hippocampus, commonly known as the sea horse, is a type of fish that has a bony skeleton. Therefore, it falls under the class **Osteichthys**, which is the class of bony fishes.

### Step 4: Eliminate the incorrect options.
- **Egnatha** is incorrect because sea horses are not jawless fishes.
- **Chondrichthys** is incorrect because sea horses are not cartilaginous fishes.
- **Mammals** is incorrect as sea horses are not mammals; they are aquatic animals.

### Conclusion:
The correct answer is **Osteichthys**.

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