Final answer:
An adverse prognosis in the post-myocardial infarction (MI) patient includes frequent angina during exercise (D). This indicates that the heart is not able to meet the increased oxygen demand.
Step-by-step explanation:
An adverse prognosis in the post-myocardial infarction (MI) patient includes frequent angina during exercise (D). After an MI, the heart muscle may be damaged, leading to reduced blood flow and oxygen supply to the heart. This can result in angina, which is chest pain or discomfort caused by a lack of oxygen to the heart muscle. When angina occurs during exercise, it suggests that the heart is not able to meet the increased oxygen demand, indicating a poor prognosis.