Which of the following is incorrect?

Options

A. Unicellular organisms have independent existence
B. Antony van leeuwenhoek first saw and described a living cell
C. Robert brown discovered the nucleus
D. cell theory was proposed by two british scientists schleiden and rudolf virchow

Answer

To solve the question of identifying the incorrect statement regarding cell theory and the history of cell discovery, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks us to identify which of the given statements is incorrect. This means we need to evaluate each statement carefully.

2. **Review the Concepts**:
- **Unicellular Organisms**: These are organisms made up of a single cell, and they can indeed exist independently. This statement is correct.
- **Discovery of Living Cells**: Anthony Van Leeuwenhoek is credited with the first observation of living cells. This statement is also correct.
- **Robert Brown's Contribution**: Robert Brown discovered the nucleus within the cell, which is a significant contribution to cell biology.
- **Cell Theory**: The cell theory was formulated by two scientists, Schleiden and Schwann, who stated that all living organisms are made up of cells. Rudolf Virchow later contributed to this theory by stating that all cells arise from pre-existing cells, modifying the original theory.

3. **Evaluate Each Statement**:
- If the statement mentions that unicellular organisms have independent existence, it is correct.
- If it states that Anthony Van Leeuwenhoek discovered living cells, it is also correct.
- If it mentions Robert Brown's discovery of the nucleus, it is correct.
- If it states that Rudolf Virchow was one of the original proposers of the cell theory, this is incorrect because he modified the existing theory rather than proposing it.

4. **Identify the Incorrect Statement**: Based on the evaluation, the statement regarding Rudolf Virchow is incorrect as he did not propose the original cell theory but modified it.

5. **Conclusion**: The incorrect statement is the one that attributes the original cell theory to Rudolf Virchow.

### Final Answer:
The incorrect statement is the one that claims Rudolf Virchow was one of the original proposers of the cell theory.

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