Assertion :- Apoplast, the system of adjacent cell walls is not continuous throughout plant.
Reason:- It is interrupted by lignified casparian strips

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that the apoplast, which is the system of adjacent cell walls in plants, is not continuous throughout the plant. This means that there are interruptions in the pathway that water and nutrients would typically follow through the cell walls.

2. **Understanding the Reason**: The reason provided is that the apoplast pathway is interrupted by lignified Casparian strips. Casparian strips are bands of cell wall material that are impregnated with lignin, making them impermeable to water and solutes.

3. **Explaining the Apoplast Pathway**: The apoplast pathway allows for the movement of water and solutes through the cell walls and spaces between cells. However, this pathway is not continuous throughout the plant due to the presence of the Casparian strips.

4. **Role of Casparian Strips**: The Casparian strips are located in the endodermis of the root and serve as a barrier to the apoplast pathway. When water reaches the endodermis, it cannot continue through the cell walls due to the Casparian strips, which forces the water to enter the symplast pathway (the pathway through the cytoplasm of the cells).

5. **Conclusion**: Both the assertion and the reason are correct. The assertion is true because the apoplast pathway is indeed interrupted at the Casparian strips, and the reason correctly explains why the apoplast is not continuous throughout the plant.

### Final Answer:
Both the assertion and the reason are correct, and the reason explains the assertion.