$ Rudolf Virchow was the first to propose that new cells arise only from the pre-existing cells.
! Dividing cells have a low content of DNA.

Options

A. If both As and R are correct and R is correct explanation of As
B. If both As and R are correct but R is not correct explanation of As
C. If As is correct, R is wrong
D. If both As and R are wrong.

Answer

To solve the question regarding Rudolf Virchow's assertion and the reason provided, we will break it down step by step.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Rudolf Virchow was the first to propose that new cells arise only from pre-existing cells."
- This statement is a well-known fact in biology and is true. Rudolf Virchow indeed proposed the idea of "Omnis cellula e cellula," meaning all cells come from existing cells.

**Hint**: Recall the historical contributions of Rudolf Virchow in cell theory.

2. **Understanding the Reason**:
- The reason given is "Dividing cells have a low content of DNA."
- This statement is false. When cells divide (either through mitosis or meiosis), the DNA content is maintained. Each daughter cell receives an equal amount of DNA as the parent cell.

**Hint**: Consider what happens to DNA during cell division and the concept of genetic material distribution.

3. **Evaluating the Relationship**:
- Now we need to evaluate the relationship between the assertion and the reason. The assertion is true, but the reason is false.
- The reason does not provide a correct explanation for the assertion since it incorrectly describes the DNA content of dividing cells.

**Hint**: Think about how to determine if the reason supports or contradicts the assertion.

4. **Checking the Options**:
- We need to analyze the provided options based on the truth values of the assertion and reason.
- The first option states both are correct and the reason explains the assertion, which is incorrect.
- The second option states both are correct but the reason does not explain the assertion, which is also incorrect.
- The third option states the assertion is correct and the reason is wrong, which is true.

**Hint**: Review the definitions of assertion and reason in the context of logical statements.

### Conclusion:
Based on the analysis, the correct answer is that the assertion is true, and the reason is false. Therefore, the third option is the correct choice.

### Final Answer:
The assertion is true, and the reason is false. The correct answer is option 3.

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