Pancreas is absent in

Options

A. Cyclostomata
B. Chondrichthyes
C. Osteichthyes
D. Gnathostomata

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which group of animals does not have a pancreas.

2. **Analyzing the Options**:
- **Option A: Cyclostomata**: This group includes jawless fish such as hagfish and lampreys. They are known to lack a pancreas.
- **Option B: Chondrichthyes**: This group includes cartilaginous fish like sharks and rays. They possess a pancreas.
- **Option C: Osteichthyes**: This group includes bony fish. They also have a pancreas.
- **Option D: Nematostomata**: This group includes jaw-bearing vertebrates, which also possess a pancreas.

3. **Identifying the Correct Answer**: Based on the analysis, Cyclostomata is the only group listed that is known to lack a pancreas.

4. **Conclusion**: Therefore, the correct answer to the question "Pancreas is absent in" is **Cyclostomata**.

---