You are presented with the quiz "What make the stem or root grow larger in diameter?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "secondary meristem is located within and around the vascular tissues" and "secondary meristems make the stem or root grow larger in diameter". So, what's the best answer to the question?

Choose from:
A). heart cells.
B). rainfall.
C). bending light rays.
D). vascular tissues.
E). tissue boxes.
F). plant cells.
G). colors of the spectrum.
H). Exfoliation.
Answer:
D).