This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Plastic & Reconstructive Surgery, Subject name: Surgery
[{'content': 'Bedsore is an example of: \nSelect and explain. \nA. Tropical ulcer, B. Trophic ulcer, C. Venous ulcer, D. Post thrombotic ulcer', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. (b) Trophic ulcer* Bedsore is a pressure ulcer. Most common in sacrum site due to persistent pressure in the back.* This is a type of trophic ulcer.* This can be prevented by frequent change of positioning of the bedridden patient and using Water/Aqua bed.* Once bedsore is formed it is difficult to treat.* Treatment extends from local wound debridement to flap procedures.', 'role': 'assistant'}]