Basic unit of life is

Options

A. Cell
B. Tissue
C. Organ
D. Organ system

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the basic unit of life. This implies we need to identify the smallest structural and functional unit that can perform all life processes.

2. **Identifying Options**: The options provided are:
- A) Cell
- B) Tissue
- C) Organ
- D) Organ system

3. **Analyzing Each Option**:
- **A) Cell**: A cell is the smallest unit of life that can carry out all necessary life functions such as metabolism, growth, and reproduction.
- **B) Tissue**: Tissues are groups of similar cells that work together to perform a specific function. They are made up of cells, so they cannot be the basic unit of life.
- **C) Organ**: Organs are composed of different types of tissues working together. Like tissues, they are not the basic unit of life.
- **D) Organ system**: An organ system is a group of organs that work together to perform complex functions. It is made up of organs, so it is not the basic unit of life.

4. **Conclusion**: Since the cell is the smallest unit that can perform all life processes independently, it is considered the basic unit of life.

5. **Final Answer**: Therefore, the correct answer is **A) Cell**.

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