Assertion :- Yeast can progress through the cell cycle in only about 90 minutes.
Reason :- Duration of cel cycle can vary from organism to organism

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is False.
D. If both Assertion & Reason are false.

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that "Yeast can progress through the cell cycle in only about 90 minutes." This means that the entire process of cell division in yeast is relatively quick compared to other organisms.

2. **Understanding the Reason**: The reason provided is "Duration of cell cycle can vary from organism to organism." This indicates that different organisms have different lengths of time for their cell cycles.

3. **Evaluating the Assertion**: The assertion about yeast is indeed correct. Yeast cells can complete their cell cycle in approximately 90 minutes, which is significantly shorter than the cell cycle duration in many other organisms.

4. **Evaluating the Reason**: The reason is also correct. The duration of the cell cycle varies widely among different organisms. For example, in humans, the cell cycle can take much longer, with the G1 phase alone lasting around 24 hours.

5. **Connecting Assertion and Reason**: Since both the assertion and the reason are true, we need to determine if the reason correctly explains the assertion. The reason does explain the assertion because it highlights that the short duration of the cell cycle in yeast does not apply universally to all organisms.

6. **Conclusion**: Both the assertion and the reason are true, and the reason is a correct explanation of the assertion.

### Final Answer:
Both assertion and reason are true, and the reason is a correct explanation of the assertion.

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