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': 'The flow in the affected perforator in case of varicose veins is \nSelect and explain. \nA. From superficial to deep, B. From deep to superficial, C. No flow, D. Can be both directions', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Physiologically flow is from superficial to deep veins, valves prevent flow back into superficial system. When perforator becomes affected in varicose veins, valves are dysfunctional and flow occurs from deep to superficial veins. Reference: Bailey and love, 27th edition, page 971', 'role': 'assistant'}]