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
In argininosuccinase deficiency, what should be supplemented to continue the urea cycle ? 
Select and explain. 
A. Aspaate, B. Arginine, C. Citrullin, D. Argininosuccinate
B: Arginine
Answer: B: Arginine 
Explanation: Argininosuccinase (argininosuccinate lyase) catalyses the cleavage of arginiosuccinate into arginine and fumarate. o Thus, in argininosuccinase deficiency arginine cannot be produced. Supplementation with arginine base helps replenish this amino acid.