The walls of cork cells are thickened by the deposition of an organic substance which make these cells impermeable to water and gases. This substance is

Options

A. Pectin
B. Suberin
C. Lignin
D. None of these.

Explanation

**Step-by-Step Solution:**

1. **Understanding Cork Cells**: Cork cells are specialized cells found in the outer layer of stems and roots of plants. They are known for their thick walls and are typically dead at maturity.

2. **Composition of Cork Cell Walls**: The walls of cork cells are thickened by the deposition of an organic substance. This thickening is crucial for the cell's function.

3. **Function of the Organic Substance**: The organic substance deposited in the walls of cork cells makes them impermeable to water and gases. This property is essential for preventing water loss and protecting the plant from external environmental factors.

4. **Identifying the Substance**: The specific organic substance that thickens the walls of cork cells and provides impermeability is known as subarin.

5. **Conclusion**: Therefore, the answer to the question is that the substance making cork cells impermeable to water and gases is **subarin**.

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