Regeneration can be observed in

Options

A. a) Fungi
B. b) Planaria
C. c) Hydra
D. d) More than one option is correct

Answer

### Step-by-Step Solution:

1. **Understanding Regeneration**:
- Regeneration is the biological process where an organism can regrow lost or damaged parts. The term "regeneration" can be broken down into "re-" meaning again, and "generation" meaning formation.

2. **Identifying Organisms**:
- The question provides four options: fungi, planaria, hydra, and states that more than one option could be correct.

3. **Analyzing Each Option**:
- **Fungi**: Fungi do not exhibit regeneration in the same way that animals do. They reproduce through spores and do not regenerate lost parts.
- **Planaria**: Planaria are flatworms known for their remarkable regenerative abilities. If a planarian is cut into pieces, each piece can regenerate into a complete organism.
- **Hydra**: Hydra are small, freshwater organisms that also possess the ability to regenerate. They can regenerate lost body parts and even reproduce asexually through budding.
- **More than one option is correct**: Since both planaria and hydra can regenerate, this option is also valid.

4. **Conclusion**:
- Since regeneration is observed in both planaria and hydra, the correct answer is "more than one option is correct." Therefore, option D is the right choice.

### Final Answer:
- The correct answer is **more than one option is correct** (Option D).

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