A middle-aged male complains of a non-productive cough for t…

A middle-aged male complains of a non-productive cough for the past 6 weeks that worsens when he is in a supine position. He reports episodes of heartburn, which he self-treats with an over-the-counter antacid that no longer seems to help his symptoms. He states he chews mints for his “bad breath”. Which of the following is the most likely cause for the patient’s cough?