This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Molecular Genetics, Subject name: Biochemistry
A 7-year-old boy with compulsive self mutilation, intellectual disability. He is always strapped to bed Serum uric acid level is elevated. What is the enzyme deficiency in this disorder? 
Select and explain. 
A. PRPP Synthetase, B. Xanthine oxidase, C. Hypoxanthine Guanine Phosphoribosyl transferase, D. Glucose 6 Phosphatase
C: Hypoxanthine Guanine Phosphoribosyl transferase
Answer: C: Hypoxanthine Guanine Phosphoribosyl transferase 
Explanation: Ans. C. Hypoxanthine Guanine Phosphoribosyl transferaseIdentifying features* Seen only in males* Compulsive self mutilation* Intellectual siability* Hyperuricemia