Which of the following muscle is not supplied by recurrent laryngeal nerve

All the muscles which move the vocal cord ( abductors, adductors or tensors) are supplied by the recurrent laryngeal nerve except for the cricothyroid muscle. The latter receives its innervation from the external laryngeal nerve which is a branch of superior laryngeal nerve. Ref: PL Dhingra Textbook of Ear, Nose and Throat, Edition 7, page - 337