Answer the following question given this paragraph: 

25.5 Physiology of Urine Formation The entire volume of the blood is filtered through the kidneys about 300 times per day, and 99 percent of the water filtered is recovered. The GFR is influenced by hydrostatic pressure and colloid osmotic pressure. Under normal circumstances, hydrostatic pressure is significantly greater and filtration occurs. The hydrostatic pressure of the glomerulus depends on systemic blood pressure, autoregulatory mechanisms, sympathetic nervous activity, and paracrine hormones. The kidney can function normally under a wide range of blood pressures due to the autoregulatory nature of smooth muscle.


Q: The entire volume of what is filtered through the kidneys about 300 times per day?

 Choices:

- gastric juice

- urine

- saliva

- blood

A:
blood
