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: Radiology
[{'content': 'Cork–screw opperance of esophagus is seen – \nSelect and explain. \nA. Achalasia cardia, B. Carcinoma esophagus, C. Diffuse esophageal spasm, D. Caustic injury', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Esophageal curling/corkscrew oppearance is seen in diffuse esophageal spasm.', 'role': 'assistant'}]