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: ENT
[{'content': 'True regarding "Preauricular sinus" is: \nSelect and explain. \nA. Improper fusion of auricular tubercles, B. Persistent opening of first branchial arch, C. Autosomal recessive pattern, D. All', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Failure of fusion of 1" and 2nd arch leads to the formation of preauricular sinus. It is commonly seen at the root of helix It is a blind track lined by squamous epithelium It may get repeatedly infected causing purulent discharge Abscess may also form Treatment is surgical excision of the track if the sinus gets repeatedly infected.', 'role': 'assistant'}]