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 regarding what distinguishes living organisms from non-living things, we can break down the solution into several steps:

### Step-by-Step Solution:

1. **Understanding Living vs. Non-Living**:
- Begin by recognizing that living organisms exhibit certain characteristics that non-living things do not. These characteristics include growth, reproduction, response to stimuli, metabolism, and cellular organization.

2. **Identifying the Basic Unit of Life**:
- The fundamental unit that defines all living organisms is the cell. All living organisms are made up of cells, which are the smallest structural and functional units of life.

3. **Types of Cells**:
- There are two main types of cells: prokaryotic and eukaryotic. Prokaryotic cells are simpler and do not have a nucleus (e.g., bacteria), while eukaryotic cells are more complex and contain a nucleus (e.g., plant and animal cells).

4. **Cellular Organization**:
- Living organisms can be unicellular (composed of a single cell, like bacteria) or multicellular (composed of multiple cells, like humans and plants). This cellular organization is crucial for the functioning of living organisms.

5. **Conclusion**:
- Therefore, the presence of cells is what distinguishes living organisms from non-living things. This is the key factor that defines life.

### Final Answer:
The presence of **cells** is what makes an organism living, while non-living things lack this cellular structure.

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