risk of coronary heart disease is the same as that of a nonsmoker
carbon monoxide level in blood drops to normal
risk of dying from lung cancer is about half that of a smoker’s
risk of having a stroke is reduced to that of a nonsmoker’s
Number 2 is correct.
Within 12 months after quitting, the carbon monoxide level in a smoker’s blood drops to normal. At 15 years after quitting, the risk of coronary heart disease is the same as that of a nonsmoker. At 10 years after quitting, the risk of dying from lung cancer is about half that of a smoker’s. At 5 to 15 years after quitting, the risk of having a stroke is reduced to that of a nonsmoker’s.