This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Diseases of orbit, Lids and lacrimal apparatus, Subject name: Ophthalmology
[{'content': "Sign of thyroid ophthalmopathy - \nSelect and explain. \nA. Von Graefe's sign, B. Dalrymple's sign, C. Gifford's sign, D. All of the above", 'role': 'user'}, {'content': "Answer: D \nExplanation: von Graefe's sign - lid lag Dalrymple&;s sign - Retraction of upper lid producing staring and frightening appearance. Most common C/f. Gifford&;s sign - difficulty inversion of upper lid. Stellwag&;s sign - infrequent blinking. Ref: AK Khurana 6thE pg414", 'role': 'assistant'}]