PLE-154

A 76-year-old male went to your clinic secondary to a productive cough, weight loss, and voice changes. He was a smoker with a 50 pack-year history and a drinker of alcoholic beverages. An X-ray was done, showing a suspicious mass at the left upper lobe of the lung. A follow-up CT scan showed a probable lung carcinoma with mediastinal lymphadenopathies compressing the left bronchial airway. Which of the following laryngeal muscles will be spared by this condition?