This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Misc., Subject name: Pathology
[{'content': 'Size of fibrillary proteins in amyloidosis: \nSelect and explain. \nA. 0-5 nm, B. 7.5-10 nm, C. 12-17 nm, D. 18-20 nm', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. b (7.5-10 nm). (Robbin Pathologic Basis of Diseases 5th/231)PHYSICAL NATURE OF AMYLOID# By electron microscopy, amyloid is seen made up largely of non-branching fibrils of indefinite length and a diameter of approximately 7.5 to 10 nm.# X-ray crystallography and infrared spectroscopy demonstrate a characteristic cross (3-pleated sheet conformation.# Chemical nature:- AL (amyloid light chain)- AA (amyloid associated)- AB (Alzheimer's disease)", 'role': 'assistant'}]