This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: miscellaneous, Subject name: Biochemistry
Molecular change in Lysosomal storage disorder is 
Select and explain. 
A. Defective fusion of lysosomes and phagosomes, B. Increased synthesis of some substrates, C. Mutation of genes encoding lysosomal hydrolases, D. Membrane defect of lysosomes
C: Mutation of genes encoding lysosomal hydrolases
Answer: C: Mutation of genes encoding lysosomal hydrolases 
Explanation: Mutation(s) in a gene encoding a lysosomal hydrolase involved in the degradation of one or more GAGsAccumulation of substrate in various tissues, including liver, spleen, bone, skin, and central nervous systemDefective lysosomal hydrolaseThe metabolic block, as in the case of the mucolipidoses.Hyaluronidase is one impoant enzyme involved in the catabolism of both hyaluronic acid and chondroitin sulfate. It is a widely distributed endoglycosidase thatcleaves hexosaminidase linkages.From hyaluronic acid, the enzyme will generate a tetrasaccharide with the structure (GlcUAb-1,3-GlcNAc-b-1,4)2, which can be degraded fuher by a b-glucuronidase and b-N-acetylhexosaminidase.A genetic defect in hyaluronidase causes MPS IX, a lysosomal storage disorder in which hyaluronic acid accumulates in the joints