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
Products of uronic acid pathway in human beings are all EXCEPT: 
Select and explain. 
A. Vitamin C, B. Pentoses, C. NADH, D. Glucuronic acid
A: Vitamin C
Answer: A: Vitamin C 
Explanation: Humans cannot synthesize vitamin C due to deficiency of enzyme, L-Gulonolactone Oxidase Uronic acid pathway in humans