Leisl has been a cigarette smoker for 8 years, and currently smokes between 1 and 2 packs of cigarettes per day. She has not yet developed any significant lung diseases, such as cancer or emphysema, but she has decided to quit smoking. After she succeeds, her body will start healing itself. Within several years, which of the following will be the most important benefit of her decision to give up cigarettes? Her risk of premature death will drop to match that of a person who has never smoked. Her risk of lung cancer will be cut in half. Her risk of developing nicotine-induced dementia will be completely eliminated. Her risk of developing emphysema will drop by approximately 40%.