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: Orthopaedics
Marfan syndrome is due to 
Select and explain. 
A. Fibrillin 1 defect, B. Fibrillin 2 defect, C. Fibrillin 3 defect, D. Fibrillin 4 defect
A: Fibrillin 1 defect
Answer: A: Fibrillin 1 defect 
Explanation: None