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': 'Amount of coronary flow per minute is? \nSelect and explain. \nA. 225 ml, B. 250 ml, C. 50 ml, D. 300 ml', 'role': 'user'}, {'content': 'Answer: B \nExplanation: B i.e. 250 ml/min', 'role': 'assistant'}]