This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Larynx, Subject name: ENT
[{'content': 'Thumb Sign is seen in- \nSelect and explain. \nA. Epiglottitis, B. Layngitis, C. CA Larynx, D. Mediastinitis', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Epiglottitis o Thumb sign (thickening of epiglottis) and vallecula sign are seen in epiglottitis.", 'role': 'assistant'}]