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
Which is the product excreted unchanged in catabolism of pyrimidine? 
Select and explain. 
A. Uric acid, B. NH3, C. Pseudouridine, D. Beta alanine
C: Pseudouridine
Answer: C: Pseudouridine 
Explanation: Pseudouridine is excreted unchanged as it cannot be catabolized in human.