This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Kidney and ureter, Subject name: Surgery
Most common renal stone: 
Select and explain. 
A. Calcium oxalate stone, B. Uric acid stone, C. Staghorn calculi, D. Cysteine stone
A: Calcium oxalate stone
Answer: A: Calcium oxalate stone 
Explanation: Calcium oxalate MC type of kidney stone (85%) Risk factor are hypercalciuria, hypercalcemia, hyperoxaluria Have hard, small and jagged surface. On section-wavy concentric laminae