A) Incorrect. Elevated creatinine levels are not specific to dehydration and fluid deficit, although dehydration can contribute to prerenal acute renal failure.

B) Incorrect. Elevated creatinine levels do not suggest normal kidney function. Instead, they indicate impaired kidney function and acute kidney injury.

C) Correct. Creatinine is a waste product produced by muscles and excreted by the kidneys. Elevated creatinine levels are a reliable indicator of acute kidney injury and impaired kidney function.

D) Incorrect. Elevated creatinine levels can be seen in both acute and chronic kidney diseases, but they are not exclusively seen in chronic kidney disease.