This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pathology, Subject name: Pathology
[{'content': 'A 43 year-old woman presents with several year history of progressive abdominal colic and constipation. Colonic biopsy stained with Congo Red and polarizing microscopy reveals the following appearance. This is due to which of the following protein propeies? \nSelect and explain. \nA. Ability to bind to oxygen, B. Beta pleated sheet teiary structure, C. Electrophoretic mobility, D. Hydroxyproline content', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Staining characteristics of amyloid Stain on gross H&E Metachromatic stains (Rosaniline dyes) Congo red & polarised light Flourescent stains Immunohistochemistry Non-specific stains Staining characteristics of amyloid Congo red & polarised light For amyloid of all types Used on both gross & microscopy Pink red color Stained section in polarised light - apple green birefringence d/t ss pleated sheet', 'role': 'assistant'}]