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
Composition of Hyaluronic acid 
Select and explain. 
A. N-acetyl glucosamine + b glucosamine acid, B. N-acetyl glucosamine + b-glucoraunic acid, C. N-acetyl glucosamine + sulfated glucosamine acid, D. N-acetyl glucosamine + iduranic acid
B: N-acetyl glucosamine + b-glucoraunic acid
Answer: B: N-acetyl glucosamine + b-glucoraunic acid 
Explanation: Composition of hyaluronic acid: repeating units of N-Acetyl-glucosamine and beta-1,4-Glucuronic acid.Ref: DM Vasudevan, 7th edition, page no: 80