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': 'Patients with syncope cannot maintain sufficient cardiac output to meet peripheral perfusion demands. Which of the following BEST describes cardiac output? \nSelect and explain. \nA. Cardiac output = end diastolic volume - end systolic volume, B. Cardiac output = hea rate X mean aerial pressure, C. Cardiac output = hea rate X stroke volume, D. Cardiac output = stroke volume X mean aerial pressure', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Cardiac output = hea rate X stroke volume: is the correct answer. 1st Choice is incorrect: Stroke volume = end diastolic volume - end systolic volume 2nd Choice is incorrect: Double product (estimation of cardiac work) = mean aerial pressure X hea rate 4th Choice is a nonsense distractor Ref: Mohrman D.E., Heller L.J. (2010). Chapter 3. The Hea Pump. In D.E. Mohrman, L.J. Heller (Eds), Cardiovascular Physiology, 7e.', 'role': 'assistant'}]