Answer:
D. Chest discomfort not relieved by rest or nitroglycerin
Explanation:
According to my research based on studies from different medical professionals, I can say that a patient shows signs of a possible myocardial infarction if the chest discomfort not relieved by rest or nitroglycerin. This is because normal chest pains caused by gas bubbles or small illnesses (common cold) will go away with a little bit of time while heart related chest pains except for heart attacks will go away with nitroglycerin which helps widen the blood vessels so more blood gets to your heart muscle.
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