Which of the following medications is administered during an acute ST-elevation myocardial infarction and continued indefinitely after?

A. Morphine is used for pain relief and to reduce stress on the heart during an acute myocardial infarction but is not continued indefinitely. B. Heparin is an anticoagulant used during an acute myocardial infarction but is not used long-term; it is typically administered during hospitalization. C. Streptokinase is a thrombolytic agent used to dissolve clots during an acute myocardial infarction but is not continued after the initial treatment. D. Aspirin is an antiplatelet medication that helps prevent clot formation and is continued indefinitely after an acute myocardial infarction to reduce the risk of future events.