A: Cells of sclerenchyma have thickened secondary walls.
R: Cells have deposition of lignin.

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 "Cells of sclerenchyma have thickened secondary walls."
- Sclerenchyma is a type of plant tissue known for its supportive role, and its cells are characterized by having thickened walls.

2. **Evaluating the Assertion:**
- Sclerenchyma cells indeed possess thickened secondary walls, which provide structural support to the plant.
- Therefore, the assertion is **true**.

3. **Understanding the Reason:**
- The reason states that "Cells have deposition of lignin."
- Lignin is a complex organic polymer that is deposited in the cell walls of many plants, particularly in sclerenchyma cells.

4. **Evaluating the Reason:**
- The deposition of lignin contributes to the thickening of the secondary walls in sclerenchyma cells, making them rigid and strong.
- Thus, the reason is also **true**.

5. **Connecting Assertion and Reason:**
- The reason (deposition of lignin) explains why the assertion (thickened secondary walls) is true.
- The thickened walls of sclerenchyma cells are primarily due to the presence of lignin, which reinforces the structure.

6. **Conclusion:**
- Both the assertion and the reason are true, and the reason is the correct explanation of the assertion.
- Therefore, the correct answer is: **Both assertion and reason are true, and reason is the correct explanation of the assertion.**

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