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: Biochemistry
Mucopolysaccharide which function as a lubricant and shock absorber in synovial fluid is 
Select and explain. 
A. Heparin, B. Hyaluronic acid, C. Keratin sulphate, D. Chondroitin sulphate
B: Hyaluronic acid
Answer: B: Hyaluronic acid 
Explanation: Hyaluronic Acid:
Hyaluronic acid is an important GAG found in the ground substance of synovial fluid of joints and vitreous humor of eyes. It is also present as a ground substance in connective tissues and forms a gel around the ovum. Hyaluronic acid serves as a lubricant and shock absorbent in joints.