This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Arrhythmias, Subject name: Medicine
[{'content': 'Sinus Bradycardia is defined as heart rate of? \nSelect and explain. \nA. Less than 40/min, B. Less than 50/min, C. Less than 60/min, D. Less than 70/min', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., Less than 60/min", 'role': 'assistant'}]