Kidney stone is formed of `:-`

Options

A. Cholesterol
B. Calcium oxalate
C. Urea
D. `MgPO_(4)`

Answer

**Step-by-Step Solution:**

1. **Understanding Kidney Stones**: Kidney stones, also known as renal calculi or nephroliths, are hard deposits made of minerals and salts that form inside the kidneys.

2. **Identifying the Composition**: Kidney stones can be composed of various substances, but the most common types are made from minerals found in urine.

3. **Analyzing the Options**:
- **Cholesterol**: This is a type of fat and is not typically associated with kidney stone formation.
- **Calcium Oxalate**: This is a common component of kidney stones and is formed when calcium combines with oxalate in the urine.
- **Urea**: This is a waste product formed from the breakdown of proteins and is not a component of kidney stones.
- **MgPO3 or MgPO4**: These are magnesium phosphate compounds, which can form stones but are less common compared to calcium oxalate.

4. **Conclusion**: Based on the analysis, the most common substance that kidney stones are formed from is calcium oxalate.

5. **Final Answer**: Kidney stones are primarily formed of calcium oxalate.

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