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: Pediatrics
[{'content': 'Which of the following is the most common sustained tachyarrhythmia in children? \nSelect and explain. \nA. Ventricular tachycardia, B. Supra ventricular tachycardia, C. Atrial Flutter, D. Atrial fibrillation', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B. Supra ventricular tachycardiaSupraventricular tachycardia is the most common sustained tachyarrhythmia in children with an incidence of 1 to 4 children per thousand. Infants with SVT present with signs of congestive heart failure. Older children present with palpitations, chest discomfort and dyspnea. The ECG shows a regular rate of 220-300/min.', 'role': 'assistant'}]