A Young Adult Patient Develops a Cough Persisting Longer Than

A young adult patient develops a cough persisting longer than 2 months. The provider prescribes pulmonary function tests and a chest radiograph, which are normal. The patient denies abdominal complaints. There are no signs of rhinitis or sinusitis and the patient does not take any medications. What will the provider evaluate next to help determine the cause of this cough?

A) 24-hour esophageal pH monitoring
B) Methacholine challenge test
C) Sputum culture
D) Tuberculosis testing