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': 'Abductor of vocal cord is ___________ \nSelect and explain. \nA. Posterior cricoarytenoid, B. Cricothyroid, C. Interarytenoid, D. Lateral cricoaretynoid', 'role': 'user'}, {'content': 'Answer: A \nExplanation: INTRINSIC MUSCLES ACTING ON VOCAL CORDS: Abductors Posterior cricoarytenoid Adductors Lateral cricoarytenoid, lnterarytenoid (transverse arytenoid) Thyroarytenoid (external pa) Tensors Cricothyroid Vocalis (internal pa of thyroarytenoid) INTRINSIC MUSCLES ACTING ON LARYNGEAL INLET: Openers of laryngeal inlet Thyroepiglottic (pa of thyroarytenoid) Closers of larylngeal inlet Interarytenoid (oblique pa), Aryepiglottic (posterior oblique pa of interarytenoids)', 'role': 'assistant'}]