A: During evolution pouched mammals of Australia survived.
R: Due to lack of competition from any other mammal due to continental drift.

Options

A. If both Assertion `&` Reason are true and the reason is the correct explanation of the assertion. Then mark (1)
B. If both Assertion `&` Reason are true but the reason is not the correct explanation of the assertion, then mark (2)
C. If Assertion is true statement but Reason is false, then mark (3)
D. If both Assertion and Reason are falses statements, then mark (4)

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion (A):** The assertion states that during evolution, pouched mammals of Australia survived. This refers to marsupials, which are a group of mammals that carry and nurse their young in pouches.

2. **Evaluating the Reason (R):** The reason provided is that this survival was due to a lack of competition from other mammals, attributed to continental drift. Continental drift refers to the movement of the Earth's continents away from each other over geological time.

3. **Linking Assertion and Reason:** The assertion is true because marsupials did survive and thrive in Australia. The reason is also true, as the separation of Australia from other landmasses led to an isolated environment with minimal competition from placental mammals, which dominate other continents.

4. **Conclusion:** Both the assertion and the reason are correct. Furthermore, the reason explains why the assertion is true. Therefore, the correct conclusion is that both the assertion and the reason are valid, and the reason is an explanation for the assertion.

**Final Answer:** Both the assertion (A) and the reason (R) are correct, and the reason is the explanation for the assertion.

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