Respuesta :

I think that it's like the filtering system in water for refrigerators. imagine that your urinary tract is used to filter out unwanted contaminants and keep the blood and other organs functional, they need to release waste and the circulatory system is the best way to move the waste from one place to another. Urea is a mixture of all the waste that your body needs to excrete to keep a homeostasis in the body.
fatherbamboo

if your on study island the answer is C.  Blood flows to the kidneys. Cellular wastes are filtered from the blood and stored in the bladder until they are excreted from the body.