Which one of the following is defining property of living being

Options

A. Growth
B. Reproduction
C. Metabolism
D. Unconsciousness

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the defining property of living beings. We need to identify a characteristic that is unique to living organisms.

2. **Defining Metabolism**: Metabolism is described as the sum total of all chemical reactions occurring in living organisms. It includes processes such as digestion, respiration, and photosynthesis. These reactions are essential for the maintenance of life.

3. **Analyzing the Options**:
- **Growth**: While growth is a characteristic of living organisms, it can also occur in non-living entities (like crystals), which makes it not a defining property.
- **Reproduction**: Similar to growth, reproduction is common in living organisms but is not universal to all living beings (e.g., mules are sterile).
- **Metabolism**: This is the process that encompasses all biochemical reactions necessary for life. It is unique to living organisms.
- **Unconsciousness**: This is not a property of living beings; rather, it refers to a state of being unaware or not responsive, which does not define life.

4. **Conclusion**: Based on the analysis, metabolism is the only characteristic that is a defining property of living beings. Therefore, the correct answer is metabolism.

### Final Answer:
The defining property of living beings is **Metabolism**.

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