<prompt> The following muscle is an opener of the glottisLateral cricoarytenoidPosterior cricoarytenoidTransverse arytenoidInter arytenoids  <response>: 1. Muscles which abduct the vocal cords: only posterior cricoarytenoids safety muscles of larynx 2. Muscles which adduct the vocal cords: lateral cricoarytenoids transverse aenoid cricothyroid thyroarytenoids 3. Muscles which tense the vocal cords: cricothyroid 4.muscles which relax the vocal cords: thyroarytenoids vocalis 4. Muscles which close the inlet of the larynx oblique arytenoids aryepiglottic 5.muscles which open the inlet of larynx : Thyroepiglotticus Ref BDC volume 3; 6th edition pg 258 