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: Pathology
[{'content': 'Two siblings were diagnosed with Osteogenesis imperfecta. But their parents are normal. Mechanism of inheritance is: \nSelect and explain. \nA. Anticipation, B. Genomic imprinting, C. Germ line mosaicism, D. New mutation', 'role': 'user'}, {'content': 'Answer: C \nExplanation: . Germ line mosaicism', 'role': 'assistant'}]