This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nucleotides, Subject name: Biochemistry
The purines salvage pathway is for: 
Select and explain. 
A. Hypoxanthine & Xanthine, B. Hypoxanthine & Thymine, C. Adenine & Guanine, D. Xanthine & Guanine
C: Adenine & Guanine
Answer: C: Adenine & Guanine 
Explanation: The purines salvage pathway is for Adenine Guanine Hypoxanthine Adenosine is the only purine nucleoside which can be salvaged i.e. Adenosine gets conveed to AMP by Adenosine Kinase.