Answer:
The correct answer would be B) DNA.
DNA (deoxyribonucleic acid) makes up the genetic makeup of any cell or organism.
Controlled modifications in the gene expression of a cell are responsible for the changes required for cell differentiation.
Cell differentiation is the process by which cell changes and mature to become a specialized cell.
Cell undergoes various changes such as cell shape, size, metabolic activity, membrane potential et cetera in order to become a specialized cell. All these characters are controlled by the genome of the cell.