This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Medicine
[{'content': 'Motility disorders of the oesophagus are best diagnosed by - \nSelect and explain. \nA. Barium meal, B. Manometry, C. Radiography, D. Endoscopy', 'role': 'user'}, {'content': 'Answer: B \nExplanation: <p>Davidson&;s principles and practice of medicine 22nd edition. *Manometry confirms the high pressure ,non relaxing lower oesophageal sphincter with poor contractility of the oesophageal body .</p>', 'role': 'assistant'}]