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': '40 year old man presents with resting heart rate of 180 beats/min. Pressure-volume diagram of left ventricle is shown below. What is the cardiac output? \nSelect and explain. \nA. 5.6 L/min, B. 5.2 L/min, C. 4.8 L/min, D. 6 L/min', 'role': 'user'}, {'content': 'Answer: A \nExplanation: EDV = 130ml ; ESV = 50ml\nStroke volume = EDV -ESV = 130 - 50 = 70 ml\nCardiac output = Heart rate\xa0× Stroke Volume\n\xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0= 80\xa0× 70\n\xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0 \xa0= 5600 ml /min', 'role': 'assistant'}]