Several Years Ago, a Man Noticed a Small Mole on His

Several years ago, a man noticed a small mole on his wrist. Years later, the mole grew in size and the man was diagnosed as having metastatic melanoma. This was likely the result of:

A) a single mutation affecting one proto-oncogene in a cell.
B) a single mutation inactivating a tumor suppressor gene.
C) several mutations affecting proto-oncogenes and/or tumor suppressor genes.
D) None of the other answer options is correct-cancers arise spontaneously, independent of mutations.