This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Oesophagus, Subject name: Surgery
[{'content': 'Heller myotomy is done for: \nSelect and explain. \nA. Pyloric stenosis, B. Hirschsprung, C. Achalasia, D. DES', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. (c) AchalasiaRef Bailey 26th edition 1010* Modified Heller cardiomyotomy: Achalasia cardia* Ramstaed's pyloromyotomy: Pyloric stenosis (Congenital)* Duhamel operation: Hirschsprung disease", 'role': 'assistant'}]