Cell theory was put forward by

Options

A. Scheliden and Schwann
B. Sutton and Boveri
C. Watson and Crick
D. Darwing and Wallace

Answer

**Step-by-Step Solution:**

1. **Understanding Cell Theory**: The cell theory is a fundamental concept in biology that states:
- All living organisms are composed of one or more cells.
- The cell is the basic unit of life.
- All cells arise from pre-existing cells.

2. **Identifying the Contributors**: The question asks who put forward the cell theory. We need to identify the correct scientists from the given options:
- A. Schleiden and Schwann
- B. Sutton and Bovey
- C. Watson and Crick
- D. Darwin and Wallace

3. **Analyzing Each Option**:
- **Option A (Schleiden and Schwann)**: Matthias Schleiden and Theodor Schwann are known for their contributions to the formulation of the cell theory in the mid-19th century.
- **Option B (Sutton and Bovey)**: These scientists are not associated with the cell theory; they are known for other biological concepts.
- **Option C (Watson and Crick)**: James Watson and Francis Crick are famous for discovering the double helix structure of DNA, not for the cell theory.
- **Option D (Darwin and Wallace)**: Charles Darwin and Alfred Russel Wallace are known for their work on the theory of evolution, not the cell theory.

4. **Conclusion**: Based on the analysis, the correct answer is **Option A: Schleiden and Schwann**.

**Final Answer**: The cell theory was put forward by A. Schleiden and Schwann.

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