Division of laboour is exhibited by

Options

A. amoeba
B. hydra
C. obelia
D. both 2 and 3

Answer

**Step-by-Step Solution:**

1. **Understanding Division of Labor**: Division of labor refers to the specialization of different cells or groups of cells to perform specific functions within an organism. This concept is crucial for the survival and efficiency of multicellular organisms.

2. **Identifying Organisms**: Division of labor is primarily observed in multicellular organisms. In contrast, unicellular organisms, which consist of a single cell, do not exhibit division of labor since one cell must perform all necessary functions for survival.

3. **Evaluating the Options**:
- **Amoeba**: This is a unicellular organism. Since it consists of only one cell, it does not exhibit division of labor. Therefore, this option is incorrect.
- **Hydra**: This organism belongs to the phylum Cnidaria and is multicellular. Hydra shows division of labor due to its regenerative capabilities, allowing it to perform specialized functions. This option is correct.
- **Obelia**: Also a member of the phylum Cnidaria, Obelia has two life stages: Polyp (which is stationary) and Medusa (which is free-swimming). Both stages exhibit division of labor, making this option correct as well.

4. **Conclusion**: Based on the analysis, the organisms that exhibit division of labor are Hydra and Obelia. Therefore, the correct answer is both options 2 (Hydra) and 3 (Obelia).

**Final Answer**: Division of labor is exhibited by Hydra and Obelia (options 2 and 3).

---