You are answering a USMLE-style medical question. Question: A 67-year-old man is brought to the emergency department with severe, crushing, retrosternal chest pain for the last 45 minutes. The pain radiates to his left shoulder and is associated with sweating. The past medical history is significant for hypercholesterolemia, for which he takes lovastatin. He smoked as a youth but quit at 40 years of age. On arrival at the emergency department, the vital signs were as follows: pulse 58/min, respiratory rate 22/min, and blood pressure 90/56 mm Hg. He is sweating profusely. The jugular venous pulse is visible 2.5 cm above the sternal angle. Auscultation reveals soft S1 and S2 heart sounds with an added S4 and bilateral inspiratory crackles at the lung bases. The electrocardiogram shows ST-elevations in leads V1 and V2. A diagnosis of an anteroseptal infarction is made. The patient was given aspirin on the way to the hospital. He is started on dopamine, morphine, nitroglycerin, and streptokinase. Which of the following would be the most concerning development over the next 24h this patient? Options: A) Hemoptysis B) Easy fatigability C) Persistent ST-segment elevation D) Shortness of breath Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.