This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Imaging of Metabolic Bone Disease, Subject name: Radiology
[{'content': 'Bone within bone appearance is seen in - \nSelect and explain. \nA. GV1L, B. Osteoporosis, C. Osteopetrosis, D. Bone infarct', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., Osteopetrosis o Bone within a bone appearance may be seen in osteopetrosis.Bone within a Bone appearanceo Bone within a bone appearance is seen in : -# Normal neonate# Prostaglandin El therapy# Growth arrest/recovery lines# Heavy metal (e.g., Lead) poisoning# Bisphosphonate therapy# Hypothyroidism & Hypoparathyroidism# Sickle cell anemia# Hypercalcemia & Hypervitaminosis D# Osteopetrosis# Rickets / Osteomalacia (healed phase)# Acromegaly# Scurvy (healed phase)", 'role': 'assistant'}]