<prompt> The most specific marker of renal function is-Creatinine clearanceInsulin clearanceBlood areaSerum creatinine  <response>: Creatinine is a waste product that is produced continuously during normal muscle breakdown. ... Creatinine clearance in a healthy young person is about 95 milliliters per minute for women120 milliliters per minute for men. This means that each minute, that persons kidneys clear 95-120 mL of blood free of creatinine. Ref Harrison20th edition pg 293 