Which Individual Is Most Likely to Quit Smoking

Which individual is most likely to quit smoking?

A) Jane, who doesn't believe that smoking will cause her to get lung cancer
B) Jill, who doesn't think that lung cancer will kill her even if she does get it from smoking
C) Jeff, who believes that stopping smoking won't significantly reduce his chance of getting lung cancer
D) James, who believes that he would be able to quit smoking if he tried