This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Musculoskeletal  disorders, Subject name: Pediatrics
[{'content': "Duchnne's muscular dystrophy \nSelect and explain. \nA. X-linked dominant, B. X-linked recessive, C. Autosomal dominant, D. Autosomal recessive", 'role': 'user'}, {'content': 'Answer: B \nExplanation: Duchene muscular dystrophy is a X linked recessive disorder. Usually become symptomatic before 5 yr and may have history of delayed walking', 'role': 'assistant'}]