Answer:
D. Meristematic cell, tubular cell, xylem, stem, shoot system, rose
Step-by-step explanation:
Among these structures cells are the smallest. There are two type of cells in this question, meristematic cell & tubular cell. Meristematic cells are rapidly dividing cells therefore they are unable to grow much so they are smaller than tubular cells. Xylem is a tissue (a group of cells meant for a specialized function) which is present inside stem and serves the function of transporting water in a plant. Stem is a bigger structure than xylem but smaller than shoot system because shoot system comprises stem plus lateral branches. Last comes rose which is a flower and there are a number of flowers in a rose plant so it is the biggest structure among all these.