This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of carbohydrate, Subject name: Biochemistry
Defective enzyme in Hurler's disease? 
Select and explain. 
A. Alpha-L-Iduronidase, B. Iduronate sulfatase, C. Beta-glucoronidase, D. Beta-galactosidase
A: Alpha-L-Iduronidase
Answer: A: Alpha-L-Iduronidase 
Explanation: Type of MPS Disease Defective Enzyme 1 Hurler syndrome Iduronidase 2 Hunter syndrome Iduronate sulfatase 3 san filipo A Heparin sulfatase 3 San filipo B N-acetyl glucosamidase 3 San filipo C Glucosamine N-acetyl transferase 3 San filipo D N-acetyl glucosamine 6 sulfatase 4 Morquio syndrome N-acetyl galactosamine 6 sulfatase 6 Maroteaux lamy syndrome N-acetyl galactosamine 4 sulfatase/aryl sulfatase B 7 Sly syndrome Beta-glucoronidase