Active transport (exocytosis, endocytosis, pumps, etc.)
The most appropriate answer is Response !!
It is due to auxin present in tip of stem !!
Because the mother cell has divided to give two new daughter cells.
Pollution from a near by city is your answer ;D
The answer is B.
" The cell was first discovered by Robert Hooke in 1665 using a microscope. The first cell theory is credited to the work of Theodor Schwann and Matthias Jakob Schleiden in the 1830s."