Which one of the following muscle is functioning as tensor of vocal cord during phonation?

Major Muscles of the Larynx: Muscle Function Innervation Key Point Posterior cricoarytenoid Abducts, tenses vocal folds Recurrent laryngeal nerve Only abductor of vocal folds Lateral cricoarytenoid Adducts true vocal folds Recurrent laryngeal nerve Interarytenoid Adducts posterior glottis Recurrent laryngeal nerve Only laryngeal muscle receiving bilateral innervation Oblique arytenoids Closes laryngeal inlet during swallowing Recurrent laryngeal nerve Thyroarytenoid Adducts, tenses vocal fold Recurrent laryngeal nerve Cricothyroid Increases vocal fold tension, especially at higher pitches External branch of superior laryngeal nerve Only muscle not innervated by recurrent laryngeal nerve