Assertion :- Alstonia show whorled phyllotaxy,
Reason :- In Alstonia one leaf arises on each node.

Options

A. If both Assertion & Reason are True & Reason is a correct explanation of the Assertion.
B. If both Assertion & Reason are True & the 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 "Alstonia shows whorled phyllotaxy."
- Whorled phyllotaxy means that more than two leaves arise from a single node on the stem.

2. **Understanding the Reason:**
- The reason given is "In Alstonia, one leaf arises on each node."
- This statement is incorrect because, in whorled phyllotaxy, multiple leaves (more than two) arise from each node, not just one.

3. **Evaluating the Truth of the Statements:**
- The assertion is true because Alstonia indeed exhibits whorled phyllotaxy.
- The reason is false because it contradicts the definition of whorled phyllotaxy.

4. **Conclusion:**
- Since the assertion is true and the reason is false, the correct option is: "Assertion is true but the reason is false."