This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory infections, Subject name: Pediatrics
[{'content': 'A 4-year-old child presents to the emergency depament with high grade fever, respiratory difficulty and noisy breathing. On examination. X ray of his neck is shown below. The most probable diagnosis is? \nSelect and explain. \nA. Recurrent papillomatosis, B. Croup, C. Epiglottitis, D. Tonsillitis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The given clinical picture along with the X-ray shows thumb sign , this finding suggests a diagnosis of Acute Epiglottitis. Thumb sign is a term also used in other conditions: Thumb sign (Marfan disease) (also known as Steinberg sign): a clinical test in which the tip of the thumb is visible medial to the little finger when it is clasped in the clenched hand. Thumb sign (chordoma): a radiological sign showing a clival tumour projection indenting the pons.', 'role': 'assistant'}]