Multicellularity is useful for

Options

A. Forming protective covering
B. Keeping cell size small
C. Division of labour
D. All the above

Answer

**Step-by-Step Solution:**

1. **Understanding Multicellularity:**
- Multicellularity refers to organisms that are composed of multiple cells, as opposed to unicellular organisms which consist of a single cell. This structural complexity allows for various functions and adaptations.

2. **Analyzing the Options:**
- **Option A: Forming, protecting, covering.**
- Multicellular organisms have specialized cells that form protective layers (like skin) and structures that cover and protect the organism from environmental threats.

- **Option B: Keeping cell size small.**
- In multicellular organisms, individual cells can remain small, which is beneficial because it increases the surface area-to-volume ratio. This is crucial for efficient nutrient uptake and waste removal.

- **Option C: Division of labor.**
- Multicellularity allows for the division of labor among different types of cells. Specialized cells can perform specific functions, which enhances the overall efficiency and adaptability of the organism.

3. **Conclusion:**
- Since multicellularity contributes to forming protective structures, maintaining smaller cell sizes, and enabling division of labor, all the options provided are valid benefits of multicellularity.

4. **Final Answer:**
- Therefore, the correct answer to the question "Multicellularity is useful for" is **Option D: All of the above.**

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