Answer:
d..........,.................
B.Workplace air quality C.UV <span>exposure</span>
Proper functioning of cells is NOT a potential cause of uncontrollable cell divison. Cells originally aren't supposed to divide uncontrollably but rather under strict and controlled conditions. When your cells aren't dividing uncontrollably we can safely say that there is "less wrong" with them than when they do so. So in essence, saying that a proper functioning is not a potential cause of uncontrollable division would be correct in this case.