"I Really Think About Quitting Smoking," Michael Often Says to His

"I really think about quitting smoking," Michael often says to his friends, "but after doing it for so long I think it is too late to be of any benefit to me." What should his friends tell him?​

A) ​"You will reduce your risk of stroke and coronary heart disease to normal within 5 years of quitting smoking, so give up the cigarettes!"
B) ​"Well there's really no way to know if it would help, but you'd sure smell a lot better if you gave up the cigarettes!"
C) ​"Actually, within one year of quitting cigarettes your lungs regain their normal ability to move out mucus!"
D) ​"That's probably correct, so just keep smoking. What is most important now is that you avoid putting second-hand smoke into others' lungs."