Which are less efficient ?

Options

A. Multicellualr animals
B. Multicellular plants
C. Colonial organisms
D. Unicellular organisms

Answer

**Step-by-Step Solution:**

1. **Understanding Efficiency in Organisms**: Efficiency in biological terms often refers to how well an organism can perform necessary life functions such as growth, reproduction, and response to the environment.

2. **Types of Organisms**: The question presents four types of organisms:
- A. Multicellular animals
- B. Multicellular plants
- C. Colonial organisms
- D. Unicellular organisms

3. **Characteristics of Multicellular Organisms**:
- Multicellular organisms (both plants and animals) consist of many cells that are specialized for different functions.
- This specialization allows for a division of labor, where different cells, tissues, and organs perform specific roles, leading to greater overall efficiency in carrying out life processes.

4. **Characteristics of Unicellular Organisms**:
- Unicellular organisms are made up of a single cell that must perform all life functions independently.
- This means they have to manage all processes such as metabolism, reproduction, and response to stimuli within one cell, which can limit their efficiency.

5. **Conclusion**: Based on the analysis, unicellular organisms are less efficient compared to multicellular organisms because they lack the specialization and division of labor that multicellular organisms possess.

6. **Final Answer**: Therefore, the answer to the question "Which are less efficient?" is option D, unicellular organisms.

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