Retrogressive metamorphosis occurs in

Options

A. Hemichordata
B. Cephalochordata
C. Urochordata
D. Vertebrata

Answer

**Step-by-Step Solution:**

1. **Understanding Retrogressive Metamorphosis**:
- Retrogressive metamorphosis is a type of metamorphosis where the larval stage has more advanced characteristics compared to the adult stage.
- During development, the larva loses these advanced traits, resulting in an adult form that is either sedentary or has degenerated features.

2. **Identifying the Groups**:
- The question provides several groups:
- Pollen
- Hemichordata
- Cephalochordata
- Urochordata
- Vertebrata

3. **Analyzing Each Group**:
- **Pollen**: This is not a relevant group in the context of metamorphosis.
- **Hemichordata**: This group does not typically exhibit retrogressive metamorphosis.
- **Cephalochordata**: Members of this group do not show retrogressive metamorphosis.
- **Urochordata**: This group is known for exhibiting retrogressive metamorphosis. The larval stage has advanced features that are lost as they develop into adults.
- **Vertebrata**: This group does not demonstrate retrogressive metamorphosis.

4. **Conclusion**:
- Based on the analysis, the correct answer to the question is **Urochordata**. This group is specifically known for retrogressive metamorphosis.

**Final Answer**: Retrogressive metamorphosis occurs in **Urochordata**.

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