This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
[{'content': 'The best test to diagnose gastroesophageal reflux disease and quantify acid output is: \nSelect and explain. \nA. Esohagogram, B. Endoscopy, C. Manometry, D. 24 hr pH monitoring', 'role': 'user'}, {'content': 'Answer: D \nExplanation: "The gold standard for diagnosing and quantifying acid reflux is the 24-hr pH test." -Sabiston\nAlso, Know\nUsing 24-hour pH test an overall score is obtained. It is known as the DeMeester score.', 'role': 'assistant'}]