Which symptom is most associated with renal failure?

• A. Fever
• B. Decreased urine output
• C. Shortness of breath
• D. Cough

Answer: (B)

Renal failure disrupts the kidneys’ ability to filter waste and balance fluids, so urine production often drops. This decreased urine output—oliguria—is a direct and common sign that the kidneys aren’t functioning well. The other symptoms listed can occur for many reasons and aren’t as specifically tied to kidney failure: fever suggests infection, while shortness of breath or cough can result from various conditions, including fluid overload but aren’t as characteristic. Therefore, the symptom most associated with renal failure is decreased urine output.