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: Biochemistry
[{'content': 'Structure of proteins can be detected by all, except: \nSelect and explain. \nA. High pressure liquid chromatography (HPLC), B. SDS Page, C. NMR spectrometry, D. Crystallography', 'role': 'user'}, {'content': 'Answer: A \nExplanation: High pressure liquid chromatography (HPLC)', 'role': 'assistant'}]