<prompt> A 65 year old man presented with vocal cord palsy. He is a pan chewer since childhood. On examination, his abducting function of vocal cord is impaired. The nerve affected is:External laryngeal nerveRecurrent laryngeal nerveMandibular nerveVagus nerve  <response>: The sole abductor of the vocal cords is the posterior cricoarytenoid muscle which is innervated by recurrent laryngeal nerve. Innervation of the Vocal Cord: Muscle Nerve Adductors lateral cricoarytenoid, thyroarytenoid, interarytenoids Recurrent laryngeal adductor branch Posterior cricoarytenoid Recurrent laryngeal abductor branch Cricothyroid External laryngeal 