A: Bark is the tissue outside steler cambium.
R: Bark is formed due to the activitity of phellogen only.

Options

A. If both Assertion & Reason are true and the reason is the correct expalanation of the assertion. Then mark (1).
B. If 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 false statements, then mark (4)

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that "Bark is the tissue outside the stellar cambium." This is a true statement because bark refers to all the tissues that lie outside the vascular cambium, which includes the secondary phloem and other tissues.

2. **Understanding the Reason**: The reason states that "Bark is formed due to the activity of phellogen only." Phellogen, also known as cork cambium, is indeed responsible for producing cork cells on the outer side and secondary cortex on the inner side. However, bark is not formed solely by phellogen; it also includes contributions from the secondary phloem.

3. **Analyzing the Statements**:
- The assertion is true because bark encompasses all tissues outside the vascular cambium.
- The reason is partially true, as phellogen is involved in bark formation, but it is not the only tissue responsible for bark. The secondary phloem also contributes to the bark.

4. **Conclusion**: Since the assertion is true and the reason is only partially true (not entirely accurate), we can conclude that the assertion is correct, but the reason does not fully support the assertion.

**Final Answer**: The assertion is true, but the reason is not entirely correct.

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