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': 'Which of the following technique is used to detect the substance present in the gall bladder stones or the kidney stones? \nSelect and explain. \nA. Electron microscopy, B. X-ray diffraction, C. Fluorescence spectroscopy, D. Nuclear magnetic resonance', 'role': 'user'}, {'content': 'Answer: B \nExplanation: X-ray diffraction method is used in the analysis of urinary calculi for fast and reliable results. It even enables to determine the propotional rate of the paicular crystalline components forming the calculus. It is also used for the detection of gallstones of all types of composition such as calcium stearate, calcium bilirubinate, cholesterol, calcite or dioxycholic acid. Ref: World of Nanobioengineering: Potential Big Ideas for the Future By Amin Elsersawi, Pages 46, 48', 'role': 'assistant'}]