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: Medicine
[{'content': 'Investigation of choice for dysphagia for solids: \nSelect and explain. \nA. Barium swallow, B. Endoscopy, C. X-ray chest, D. C.T. scan', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Answer is D (Manometry) Esophageal manometry is the gold standard test for esophageal motility disorders. Esophageal Motility Disorders : Manometry is the test of choice Achalasia Cardia Diffuse Oesophageal Spasm (Discoordinated motility) Nutcracker Oesophagus (Hypercontractile motility) Hypeensive LES (Hypercontractile motility) Hypotensive LES(Hypocontractile motility) Ineffective Oesophageal motility (Hypocontractile motility)', 'role': 'assistant'}]