Petromyzon belongs to class

Options

A. Chondrichythes
B. Cyclotomata
C. Osteichthyes
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks to identify the class to which Petromyzon belongs.

2. **Identifying the Options**: The options provided are:
- A) Chondrichthyes
- B) Cyclostomata
- C) Osteichthyes
- D) Nanothyes

3. **Analyzing Each Class**:
- **Osteichthyes**: This class includes bony fishes, such as lungfishes and ray-finned fishes. Petromyzon does not belong to this class.
- **Chondrichthyes**: This class consists of cartilaginous fishes, such as sharks and rays. Petromyzon is not a cartilaginous fish.
- **Cyclostomata**: This class includes jawless fishes, which are characterized by the absence of jaws. Petromyzon is a jawless fish, thus it belongs to this class.
- **Nanothyes**: This option is not a recognized class in the context of Petromyzon.

4. **Conclusion**: Based on the analysis, Petromyzon belongs to the class Cyclostomata.

5. **Final Answer**: The correct answer is **B) Cyclostomata**.

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