Cell theory is proposed by Schleiden, Virchow, and _________

Options

A. Watson
B. Flemming
C. Schwann
D. Crick

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks for the third scientist who proposed the cell theory along with Schleiden and Virchow.

2. **Recall the Cell Theory**: The cell theory states that all living organisms are composed of cells, cells are the basic unit of life, and all cells arise from pre-existing cells.

3. **Identify the Scientists**: We know that Schleiden and Virchow are two of the scientists associated with the cell theory. The third scientist is important to identify.

4. **Review the Options**: The options provided are Watson, Fleming, Schwann, and Crick.

5. **Analyze Each Option**:
- **Watson**: Known for studying the structure of DNA, not cell theory.
- **Fleming**: Known for discovering penicillin, not related to cell theory.
- **Schwann**: He is the scientist who, along with Schleiden and Virchow, contributed to the cell theory.
- **Crick**: Also known for DNA structure, not related to cell theory.

6. **Select the Correct Answer**: Based on the analysis, the correct answer is Schwann.

**Final Answer**: Cell theory is proposed by Schleiden, Virchow, and Schwann.

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