Answer:
b. glomerular filtration rate
Step-by-step explanation:
Glomerular filtration rate is a measure of blood filtration per minute.
When blood enters the glomerulus, it has some pressure which is called outward pressure. Opposite to this pressure, inward pressure consists of colloidal osmotic pressure and capsular hydrostatic pressure.
The net filtration pressure is the difference between outward and inward pressure.
Glomerular filtration rate is highly regulated by kidneys themselves (constriction and dilatation of afferent arteriole), via neural or hormonal control (e.g. via atrial natriuretic peptide).