3. Cancer treatments often involve chemicals that arrest DNA synthesis. The cancer cells are more directly affected than noncancer cells because (A) DNA synthesis does not occur in noncancerous cells. (B) DNA synthesis occurs differently in noncancerous cells. (C) treatment with these chemicals results in the cancerous cells regaining control over the cell cycle. (D) DNA synthesis occurs less frequently in the noncancerous cells. (E) DNA synthesis occurs less frequently in the cancerous cells.