Final answer:
Creatinine is a waste product not reabsorbed in the renal tubules, and it is excreted out of the body with urine; therefore, none of the options provided (10%, 20%, 30%, 40%) accurately depict creatinine reabsorption as it is a negligible amount.
Step-by-step explanation:
The question is asking about the percentage of creatinine reabsorption by the renal tubules per day. It's important to understand that unlike substances such as glucose, amino acids, water, and electrolytes which have varying degrees of reabsorption in the nephron, creatinine is a waste product that is not reabsorbed in the renal tubules.
Creatinine is filtered by the glomerulus and then excreted out of the body with urine. Given this information, we can determine that the approximate amount of creatinine reabsorbed by the renal tubules per day is a negligible amount, which would be option (a) 10%, but from the options provided, none correctly represent that creatinine is not significantly reabsorbed by the renal tubules.