Question: A 62-year-old male has a history of GERD for the past 3-4 years. Today, he reports worsening symptoms. He has been using over-the-counter antacid tablets and a proton-pump inhibitor without relief. He denies nausea, vomiting, or weight loss. His medical history is also significant for hypertension and type 2 diabetes mellitus, managed with hydrochlorothiazide (HCTZ) and metformin (Glucophage). He has a 40-pack per year history of tobacco use. His BMI is 33, but his examination is otherwise unremarkable. Which of the following is the most appropriate management for this patient? A. Barium swallow B. Ambulatory esophageal pH monitoring C. Esophagogastroduodenoscopy (EGD) D. H2 blockers