In which of the following regeneration take place ?

Options

A. Hydra
B. Planaria
C. Both A & B
D. Human

Answer

**Step-by-Step Solution:**

1. **Understanding Regeneration**: Regeneration is a process where an organism can regrow lost parts or even form a new organism from a fragment. It is often considered a form of asexual reproduction.

2. **Analyzing the Options**:
- **Option A: Hydra**: Hydra can reproduce asexually through budding, but it does not primarily regenerate lost parts in the way we define regeneration.
- **Option B: Plenaria**: Plenaria, or planarians, are known for their remarkable ability to regenerate lost body parts. If a planarian is cut into pieces, each piece can regenerate into a complete organism.
- **Option C: Both A and B**: This option suggests that both Hydra and Plenaria can regenerate, which is incorrect because Hydra does not regenerate in the same way as Plenaria.
- **Option D: Human**: Humans do not regenerate lost body parts in the same manner as some simpler organisms. Humans primarily reproduce sexually, and while they can heal wounds, they do not regenerate limbs or organs.

3. **Conclusion**: Based on the analysis, the only organism from the options given that is capable of regeneration in the true sense is Plenaria.

4. **Final Answer**: The correct answer is **B: Plenaria**.

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