Final answer:
Among the events listed, it's most likely that a man over the age of 55 would have a heart attack due to the increased risk associated with age.
Step-by-step explanation:
When considering which of the given events is most likely, we must take into account factors such as age, lifestyle, and health conditions. Age is a significant risk factor, with a greater chance of developing cardiovascular disease as a person gets older. Tobacco smoking is another risk factor that can be controlled. Men under the age of 64 are more likely to have coronary heart disease than women, and the risk increases as they age. Since family history also plays a role, genetics cannot be ignored.
Given the risk factors and information provided, the most likely event among those listed is: (d) That a man is over 55 and has a heart attack. This is because age is a well-established risk factor, and incidence rates for heart attacks increase significantly as men pass the age of 55.