Blood cells are different than nerve cells in how they look and what they do. Why is this, since both of these kinds of cells are found in humans?

A. Blood cells started out as nerve cells but changed shape due to their location

B. Blood cells undergo apoptosis in order to fulfill their role in the body

C. The cells have differentiated to perform different tasks within the organism

D. If blood cells were long like nerve cells they would get stuck in the blood vessels