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': 'Which of the following factors affect pulse pressure? \nSelect and explain. \nA. Stroke volume, B. Compliance of aoa, C. Ejection fraction, D. All', 'role': 'user'}, {'content': "Answer: D \nExplanation: Two major factors affect the pulse pressure: (1) the stroke volume output of the hea and (2) the compliance (total distensibility) of the aerial tree. A third, less impoant factor is the character of ejection from the hea during systole. Ref: Guyton's physiology, 11th edition, page 73", 'role': 'assistant'}]