This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Urology, Subject name: Surgery
Most common renal stone is 
Select and explain. 
A. Triple phosphate, B. Calcium oxalate, C. Uric acid, D. Salicylate
B: Calcium oxalate
Answer: B: Calcium oxalate 
Explanation: Calcium oxalate stones - 60% Phosphate stones( hydroxyapatite and brushite) - 22% Uric acid stones -7 % ,struvite 7%.Cystine stones - 2% Reference : Campbell and Walsh urology 11th edition , chapter 51 , pg no 1181