The smallest units in living organism is

Options

A. Organ System
B. Tissue
C. Organ
D. Biomolecule

Answer

To answer the question "The smallest units in living organisms is," we will analyze the options provided: organ system, tissue, organ, or biomolecule.

### Step-by-Step Solution:

1. **Understanding the Options**:
- **Organ System**: This is a group of organs that work together to perform complex functions in an organism.
- **Tissue**: This is a group of similar cells that perform a specific function.
- **Organ**: This is a structure made up of different types of tissues that work together to perform a specific function.
- **Biomolecule**: This refers to any molecule that is produced by living organisms, including proteins, nucleic acids, carbohydrates, and lipids.

2. **Identifying the Smallest Unit**:
- Among the options, we need to identify which one is the smallest unit.
- Cells are the basic building blocks of all living organisms. They are the smallest structural and functional units of life.

3. **Conclusion**:
- While biomolecules are essential components of cells, the smallest unit that can be considered a living entity is the cell itself.
- Therefore, the correct answer to the question is **cell**, which is a type of biomolecule.

4. **Final Answer**:
- The smallest unit in living organisms is the **cell** (option number 4).