Assertion :- Darwin's finches are classical example of natural selection.
Reason :- Darwin explained that beak sizes and shape in finches varied according to food habit fo different finches.

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 a 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 "Darwin's finches are a classical example of natural selection." This is true because Darwin's observations of finches in the Galapagos Islands provided significant evidence for the theory of natural selection.

2. **Understanding the Reason**: The reason given is that "Darwin explained that beak sizes and shapes in finches varied according to the food habits of different finches." This is also true, as Darwin noted that the finches adapted their beak shapes and sizes to better access different types of food available in their environment.

3. **Connecting Assertion and Reason**: The reason provided explains why the assertion is true. The variation in beak size and shape among the finches is a direct result of natural selection, where those finches with beak shapes better suited to their food sources were more likely to survive and reproduce.

4. **Conclusion**: Both the assertion and the reason are true, and the reason correctly explains the assertion. Therefore, the correct answer is that both the assertion and the reason are true, and the reason is a correct explanation of the assertion.

**Final Answer**: Option A: Both assertion and reason are true, and reason is the correct explanation of the assertion.

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