Cartilaginous fishes belong to the class

Options

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

Answer

To determine which class cartilaginous fishes belong to, let's analyze the options given:

1. **Ostichthys**: This class refers to bony fishes, which are characterized by a skeleton made of bone. Examples include tuna and salmon. Since we are looking for cartilaginous fishes, this option is not correct.

2. **Agnatha**: This is a superclass that includes jawless fishes such as lampreys and hagfish. While these fishes are interesting, they do not fall under the category of cartilaginous fishes.

3. **Dipnoi**: This subclass includes lungfishes, which are a type of bony fish that can breathe air. Again, this does not relate to cartilaginous fishes.

4. **Chondrichthyes**: This class includes cartilaginous fishes, which have a skeleton made of cartilage rather than bone. Examples of Chondrichthyes include sharks and rays.

Based on this analysis, the correct answer to the question is **Chondrichthyes**.

**Final Answer**: Cartilaginous fishes belong to the class **Chondrichthyes**.

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