When an organism breaks into a number of parts and each part develop into an individual, it is called :

Options

A. Regeneration
B. Budding
C. Binary fission
D. Spore formation

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about a process where an organism breaks into several parts, and each of those parts can develop into a new individual.

2. **Identifying the Options**: The options given are:
- Regeneration
- Budding
- Binary Fission
- Small Formation

3. **Analyzing Each Option**:
- **Regeneration**: This is the process where an organism can restore or regrow lost parts. In some cases, like in certain species of starfish or hydra, if the organism is cut into pieces, each piece can regenerate into a new individual.
- **Budding**: This is a form of asexual reproduction where a new organism develops from an outgrowth or bud on the parent organism.
- **Binary Fission**: This is a form of asexual reproduction where a single organism divides into two separate organisms. This is common in unicellular organisms like bacteria.
- **Small Formation**: This term is not commonly used in biological contexts and does not refer to a known reproductive process.

4. **Conclusion**: Based on the analysis, the correct answer is **Regeneration**, as it specifically refers to the ability of an organism to regenerate lost parts and, in some cases, form new individuals from those parts.

5. **Final Answer**: When an organism breaks into a number of parts and each part develops into an individual, it is called **Regeneration**.

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