This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
[{'content': 'What is diagnostic of fresh myocardial infraction in ECG \nSelect and explain. \nA. QT interval prolongation, B. P mitrale, C. ST segment elevation, D. ST segment depression', 'role': 'user'}, {'content': 'Answer: C \nExplanation: diagnostic changes of acute or evolving ischemia are often masked by the presence of left bundle branch block, electronic ventricular pacemaker patterns, and Wolff- Parkinson-White preexcitation. However, clinicians continue to over- diagnose ischemia or infarction based on the presence of ST-segment elevations or depressions; T-wave inversions; tall, positive T waves; or Q waves not related to ischemic hea disease (pseudoinfarct pat- terns). Ref Harrison 20th edition pg 1435', 'role': 'assistant'}]