This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Carbohydrates, Subject name: Biochemistry
Mucopolysaccharide that does not contain Uronic acid residue is: 
Select and explain. 
A. Heparan Sulphate, B. Heparin, C. Chondroitin Sulphate, D. Keratan Sulphate
D: Keratan Sulphate
Answer: D: Keratan Sulphate 
Explanation: Ans. D. Keratan SulphateGAG with no Uronic Acid: Keratan SulphateGAG with no Sulfate group: Hyaluronic AcidGAG not covalently linked to Protein: Hyaluronic Acid