When you look around, you see both living and non-living things. You must have wondered and asked yourself – ‘what is it that makes an organism living, or what is it that an inanimate thing does not have which a living thing has’ ? The answer to this is the presence of -

Options

A. Cell
B. Nucleus
C. Mitochondria
D. Chloroplast

Answer

To answer the question about what distinguishes living organisms from non-living things, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Question**: The question asks what makes an organism living or what is absent in non-living things that is present in living organisms.

2. **Understanding Living Organisms**: Living organisms are characterized by certain features such as growth, reproduction, metabolism, and response to stimuli. These features are fundamentally linked to the presence of cells.

3. **Define Cells**: Cells are the basic structural and functional units of life. Every living organism is made up of cells, which can be unicellular (single-celled organisms) or multicellular (organisms made of many cells).

4. **Differentiate Between Living and Non-Living**: Non-living things do not have cells. They do not exhibit the characteristics of life such as metabolism, growth, and reproduction.

5. **Evaluate the Options**: The options provided are:
- Cell
- Nucleus
- Mitochondria
- Chloroplast

Among these, the cell is the fundamental unit of life that is present in all living organisms.

6. **Conclusion**: Therefore, the presence of cells is what makes an organism living. Non-living things lack this cellular structure and the associated life processes.

### Final Answer:
The answer to the question is the presence of **cells**.

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