Assertion :- Branching descent and Natural selection are the two key concepts of Darwinian theory of evolution.
Reason :- Darwinism is able to explain the presence of vestigeal organ.

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 "Branching descent and natural selection are the two key concepts of Darwinian theory of evolution."
- This is true because Charles Darwin's theory of evolution is fundamentally based on these two concepts. Branching descent refers to the idea that species evolve from common ancestors through a branching process, while natural selection explains how certain traits become more common in a population due to advantages in survival and reproduction.

2. **Understanding the Reason:**
- The reason states that "Darwinism is able to explain the presence of vestigial organs."
- This is false. Vestigial organs are remnants of organs that were functional in ancestors but have lost their original function in current species. Darwin's theory does not adequately explain why these organs persist if they are no longer useful.

3. **Evaluating the Relationship:**
- The assertion is true, but the reason is false. The reason does not correctly explain the assertion since Darwinism does not account for vestigial organs.

4. **Conclusion:**
- Since the assertion is true and the reason is false, the correct answer is that the assertion is true, but the reason is false.

**Final Answer:**
- Assertion is true, Reason is false.

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