This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
[{'content': 'For hiatus hernia, investigation of choice is \nSelect and explain. \nA. Barium meal follow through, B. Barium meal upper GI, C. Barium meal upper GI in Trendelenberg position, D. Barium meal double contrast', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Barium swallow and meal examination give the best appreciation of gastro-oesophageal anatomy. The patient is in the Trendelenburg position to demonstrate barium in the fundus.Bailey and Love 26th edition Pg: 1015', 'role': 'assistant'}]