Answer:
The correct option is C) Cells do not use the same sections of DNA in the same proportions, at the same time in development, which leads to differentiation.
Step-by-step explanation:
All the cells in an organisms body comprise of the same DNA. However, each cell is specialized to perform a different function because a part of the DNA which is active in one cell might not be active in the other cells. In this way, cell differentiation occurs. The genes which are being transcribed in one cell type may be completely repressed in the other cell type. As a result, variations occur in the structure and function of different cells.