Answer:
(D). Through cell division and production.
Step-by-step explanation:
Growth can be defined as increase in size, which is done by increasing the numbers of cells by multicellular organisms. It depends on division and differentiation of cells.
Cell division involves formation of two daughter cells from a single parent cell. So, by cell divisions, number of cells are increased that leads to growth of the organism.
Thus, the correct answer is option (D).