Assertion: For a better understanding of tissue organisation ofroots stems and leaves it is convenient to study the tansverse sections of the matures zones of these organs
Reason: The vertical section of a dorisventral leaf through the lamina shows three main parts , namely epidermis, mesophyll and vascular system

Answer

B

Explanation

For a better understanding of tissue organisation of roots, and leaves it is vconveninent to study the transverse secotions of the mature zones of these organs.
The vertical section of dorsiventral leaf through the lamina shows threee main parts, namely, epidermis, mesophyll and vascular system.