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': 'All are true of achalasia cardia, except: \nSelect and explain. \nA. Dysphagia, B. Aspiration pneumonitis, C. Mecholyl test is hyposensitive, D. X-ray finding of dilated esophagus with a narrow end', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. (c) Mecholyl test is hyposensitiveRef OESO/2011Internet* Mecholyl test - has been used to demonstrate hypersensitivity in LES for years and to differentiate the Achalasia from carcinoma.* It is not used nowadays.', 'role': 'assistant'}]