This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Vascular surgery, Subject name: Surgery
[{'content': 'Finding the cause of unilateral lymphedema of the leg includes -a) Taking a family historyb) Looking for chronic infection in the footc) Looking for early malignant disease of the testisd) Looking for filariasise) Performing a casoni test \nSelect and explain. \nA. acd, B. abd, C. abc, D. ab', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Lymphoedema precox is unilateral and it is a familial condition', 'role': 'assistant'}]