[A]: Plasmolysis is seen by both living and dead cells.
[R]: Both types of cell are impermeable

Options

A. (a) If both A and R are true and R is the correct explanation of A
B. (b) If both A and R are true but R is not the correct explanation of A
C. (c) If A is true and R is false
D. (d) If both A and R are false

Answer

To solve the assertion and reason question regarding plasmolysis, we will analyze both the assertion (A) and the reason (R) step by step.

### Step 1: Understand the Assertion
- **Assertion (A)**: "Plasmolysis is seen by both living and dead cells."
- **Explanation**: Plasmolysis is a process that occurs when a cell loses water in a hypertonic solution, causing the cell to shrink. This phenomenon is primarily observed in living plant cells, as they maintain their structure and function during this process. Dead cells do not exhibit plasmolysis because they lack the necessary cellular machinery to respond to osmotic changes.

### Step 2: Evaluate the Assertion
- **Conclusion**: The assertion is **false** because plasmolysis is only seen in living cells, particularly in plant cells, and not in dead cells.

### Step 3: Understand the Reason
- **Reason (R)**: "Both types of cells are impermeable."
- **Explanation**: This statement suggests that both living and dead cells do not allow substances to pass through their membranes. However, living plant cells are permeable, allowing water and solutes to move in and out, while dead cells are indeed impermeable due to the lack of a functional plasma membrane.

### Step 4: Evaluate the Reason
- **Conclusion**: The reason is also **false** because living cells are permeable while dead cells are not.

### Step 5: Final Conclusion
- Since both the assertion (A) and the reason (R) are false, the correct answer to the question is option D, which states that both the assertion and reason are incorrect.

### Summary of the Solution
- **Assertion (A)**: False (Plasmolysis is seen only in living cells).
- **Reason (R)**: False (Living cells are permeable, while dead cells are not).
- **Final Answer**: Option D (Both A and R are incorrect).