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: Surgery
[{'content': "Risk factors of pulmonary embolisma) 30 yrs female on OCP' sb) Pregnancyc) Leg paralysisd) 50 yrs person with uncomplicated cholecystectomye) Bechet's disease \nSelect and explain. \nA. bcde, B. abcd, C. acde, D. abce", 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]