Retrogressive metamorphosis is found in

Options

A. Amphioxus
B. Rana
C. Ascidia
D. Protochordata

Answer

**Step-by-Step Solution:**

1. **Understanding Metamorphosis**: Metamorphosis refers to the process of transformation that certain organisms undergo, where they change from one developmental stage to another. A common example is the transformation of a caterpillar into a butterfly.

2. **Differentiating Types of Metamorphosis**: There are two main types of metamorphosis: progressive and retrogressive. Progressive metamorphosis involves an organism developing more complex structures and features over time (like a caterpillar developing into a butterfly). In contrast, retrogressive metamorphosis involves the loss of certain characteristics or structures.

3. **Identifying Retrogressive Metamorphosis**: Retrogressive metamorphosis is characterized by the organism losing valuable or useful characteristics as it develops. This is often seen in certain marine organisms.

4. **Evaluating the Options**: The question provides four options:
- A. Amphyoxus
- B. Rana
- C. Acedia
- D. Protocordata

5. **Analyzing Each Option**:
- **Amphyoxus**: This organism does not exhibit retrogressive metamorphosis.
- **Rana**: This is a genus of frogs, which also do not show retrogressive metamorphosis.
- **Acedia**: This organism is known to undergo retrogressive metamorphosis, losing its complex structures as it matures.
- **Protocordata**: This group does not demonstrate retrogressive metamorphosis either.

6. **Conclusion**: Based on the analysis, the organism that exhibits retrogressive metamorphosis is **Acedia**. Therefore, the correct answer is option **C**.

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