Cancer can result from a variety of different mutational events. Which of the following is LEAST likely to result in the initiat
ion of a cancerous tumor? A. A receptor mutation results in activation of a cell-division pathway in the absence of the appropriate ligand.
B. A mutation results in the loss of the ability to produce a tumor-suppressor protein.
C. A defect in a cell-cycle checkpoint prevents a cell from entering the S phase
D. At the anaphase checkpoint, separation of chromatids occurs without all centromeres being attached to kinetochore microtubules from both poles.