Which patient below with acute kidney injury is in the oliguric stage of AK?

A. A 78-year-old female with respiratory acidosis, increased GFR, decreased BUN/Creatinine, hypokalemia, and urinary output of 550 mL/day: Urine output is above the oliguria threshold (less than 400 mL/day), and labs suggest improved kidney function. This patient is not in the oliguric phase. B. A 30-year-old male with metabolic acidosis, hyperkalemia, improving GFR, resolving edema, and urinary output of 4 L/day: High urine output indicates the diuretic phase of AKI. This patient is past the oliguric stage. C. A 56-year-old male who has metabolic acidosis, decreased GFR, increased BUN/Creatinine, hyperkalemia, edema, and urinary output of 350 mL/day: Urine output <400 mL/day with worsening lab values is characteristic of the oliguric phase. The kidneys are retaining waste and fluids, and metabolic disturbances are present. D. A 45-year-old female with metabolic acidosis, hypokalemia, normal GFR, increased BUN/Creatinine, edema, and urinary output of 600 mL/day: Urine output is above the oliguria threshold, suggesting the patient is in the diuretic or recovery phase rather than oliguric phase.