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: Pathology
[{'content': 'Mutations in Marfans syndrome is in: \nSelect and explain. \nA. Collagen, B. Fibrillin, C. Elastin, D. Fibrin', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Fibrillin', 'role': 'assistant'}]