C

In bilateral recurrent laryngeal nerve paralysis both vocal cords lie near the midline (paramedian/adducted), so the glottic airway is critically narrowed, producing marked stridor and dyspnea, yet voice quality is largely preserved because the cords can still approximate for phonation [Ehret 2023, PMID 37404428; Baumann 1989, PMID 2730268].