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': 'Closure of glottis is by, all except - \nSelect and explain. \nA. Posterior cricoarytenoids, B. Lateral cricoarytenoids, C. Cricothyroid, D. Thyroarytenoids', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Muscles which adduct the vocal cords (close the glottis) are thyroarytenoid, lateral cricoarytenoid, Interarytenoid (Transverse arytenoid), Cricothyroid.', 'role': 'assistant'}]