This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: DNB 2018, Subject name: Surgery
[{'content': 'Pharyngo-esophageal reflux is monitored by: \nSelect and explain. \nA. Esophageal pH monitoring, B. Double probe pH monitoring, C. Barium esophagogram, D. Radionuclide scintigraphy', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Double probe pH monitoring - Pharyngo-esophageal reflux. Esophageal PH monitoring - GERD Barium esophagogram - Frequently performed to diagnose problems related to esophageal and pharynx that present with symptoms like dysphasia. Radionuclide scintigraphy - Radiotracer injected into vein that travels to specific organ and emits gamma rays as it decays which is then recorded using Gamma camera. Used to detect normal functionality of the organ.', 'role': 'assistant'}]