Final answer:
To lower the risk of diseases including emphysema, adopting a diet rich in fruits and vegetables is advised, along with avoiding smoking and including regular exercise.
Step-by-step explanation:
The dietary habit that can lower your risk of many diseases, including emphysema, is C. A diet rich in fruits and vegetables. This type of diet provides essential nutrients that can help maintain a healthy respiratory system and reduce inflammation. Smoking is known to be the major cause of chronic respiratory diseases such as emphysema, so avoiding tobacco in any form, including secondhand smoke, is paramount. Avoiding smoking and making healthy lifestyle choices, like engaging in regular exercise and consuming a nutrient-rich diet, are crucial steps in reducing the risk of emphysema and other related health conditions.