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': 'Following are radiological evidence of Achalasia cardia Except \nSelect and explain. \nA. Beak like appearance, B. Dilated touous esophagus, C. Presence of air-fluid level, D. Exaggerated peristalsis', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Achalasia is a rare disease caused by loss of ganglion cells within the esophageal myenteric plexus.The barium swallow x-ray appearance is of a dilated esophagus with poor emptying, an air-fluid level, and tapering at the LES giving it a beak-like appearance.Ref: Harrison&;s Principles of Internal Medicine; 19th edition; Chapter 347 Diseases of the Esophagus; Page no: 1904', 'role': 'assistant'}]