This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
[{'content': 'QRS complex is due to: September 2008 \nSelect and explain. \nA. Ventricular repolarization, B. Atrial depolarization, C. Conduction through AV node, D. Ventricular depolarization', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. D: Ventricular depolarizationQRS complex is due to ventricular depolarization and atrial repolarization. Normal duration is 0.08 sec.', 'role': 'assistant'}]