Which one belongs to dipnoi?

Options

A. Lung fish
B. Cat fish
C. Rat fish
D. Star fish

Answer

To determine which organism belongs to the subclass Dipnoi, let's analyze the options provided in the question step by step.

### Step-by-Step Solution:

1. **Understand the Term Dipnoi**:
- Dipnoi refers to a subclass of fish commonly known as lungfish. They are characterized by their ability to breathe air using lungs in addition to gills.

2. **Evaluate the Options**:
- **Option A: Lungfish**:
- Lungfish are indeed part of the subclass Dipnoi. They are freshwater fish known for their primitive characteristics among bony fishes. They possess both lungs and gills, allowing them to survive in low-oxygen environments.
- **Option B: Catfish**:
- Catfish belong to the class Actinopterygii, which includes ray-finned fishes. They do not belong to Dipnoi.
- **Option C: Ratfish**:
- Ratfish, also known as chimeras, belong to the class Chondrichthyes, which includes cartilaginous fishes. They are not part of Dipnoi.
- **Option D: Starfish**:
- Starfish are echinoderms and do not belong to the fish category at all. They are not related to Dipnoi.

3. **Conclusion**:
- Based on the analysis, the only organism from the options that belongs to Dipnoi is **Lungfish**.

### Final Answer:
The organism that belongs to Dipnoi is **Lungfish**.

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