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: Surgery
[{'content': 'In achalasia cardia, true is - \nSelect and explain. \nA. Pressure at distal end increased with no peristalsis, B. Low pressure at LES with no peristalsis, C. Pressure > 50 mm Hg with peristalsis, D. Pressure at the distal end increased with normal relaxation', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The pressure is elevated at LES with incomplete relaxation on deglutition. The normal pressure of LES is 13.8 ±4.6 of Hg. In Achlasia it increases to twice normal.\n\nAlso know\n\nHypertensive Lower esophageal sphincter\n\nis another motor disorder distinct from Achalsia\nhere the LES pressure is elevated but it relaxes normally. Peristalsis in the esophageal body is also normal.', 'role': 'assistant'}]