Which Statement Best Explains the Process of Filtration in the Nephron

Multiple Choice

Which statement best explains the process of filtration in the nephron?

A) Filtration occurs as a result of passive and active transport mechanisms from all parts of the renal tubules; a major portion of reabsorption occurs in the proximal tubule.
B) Filtration is the movement of molecules out of peritubular blood and into the tubule for excretion.
C) Filtration is the movement of molecules out of the tubule and into peritubular blood.
D) Filtration is the movement of water and protein-free solutes from plasma in the glomerulus into the capsular space of Bowman capsule.