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: Radiology
[{'content': 'Rare orbit sign is seen in: \nSelect and explain. \nA. NF I, B. NF II, C. Sturge weber syndrome, D. Tuberous sclerosis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. NF I', 'role': 'assistant'}]