This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolic and endocrine disorders, Subject name: Orthopaedics
[{'content': "which of the following is Marble bone disease ? \nSelect and explain. \nA. Osteoporosis, B. Paget's disease, C. Osteopetrosis, D. Osteogenesis imperfecta", 'role': 'user'}, {'content': "Answer: C \nExplanation: *Osteopetrosis is also known as marble bone disease or Albers- Schonberg disease. *Paget's disease is known as Osteitis deformans. *Osteogenesis imperfecta is known as Brittle bone disease. *Osteoporosis is known as Fragile bone disease. Ref: Maheshwari 9th/e p.307", 'role': 'assistant'}]