Answer: Bile
Step-by-step explanation:
Kidney stones can be defined as substances which is formed by the accumulation of different substances to form a stone.
The chemical nature of the stone depends on the chemical imbalance that is found inside urine.
There are almost 5 common types of stone which is made of calcium oxalate, calcium phosphate, cystine, uric acid and struvite.
Hence, the correct answer is option D