Final answer:
The assertion that the higher risk difference for coronary heart disease compared to lung cancer in smokers is due to the disease's prevalence is false. It is influenced by how smoking affects the incidence of each disease. Hence, option (b) false is the correct answer.
Step-by-step explanation:
The statement that the risk difference associated with cigarette smoking is much higher for coronary heart disease than lung cancer because coronary heart disease is a more common disease than lung cancer is false. While it is true that smoking significantly increases the risk for both diseases, the heightened risk is not solely because one disease is more common. The risk difference is also a function of the degree to which smoking influences the incidence of each disease.
Smoking is a well-known cause of various cancers, but it also is a major cause of cardiovascular diseases. Smoking introduces carcinogens into the lungs, which is a direct cause of lung cancer. However, the negative effects of smoking on the cardiovascular system, like high blood pressure and blood clots, increase the risk of coronary heart disease as well. Both are serious health concerns linked to smoking.