This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pharmacology
A female patient has dysphagia, intermittent epigastric pain. On endoscopy, oesophagus was dilated above and narrow at the bottom. Treatment is(not related-surgery) 
Select and explain. 
A. PPI, B. Dilatation, C. Esophagectomy, D. Heller's cardiomyotomy
D: Heller's cardiomyotomy
Answer: D: Heller's cardiomyotomy 
Explanation: .