Answer:
d. cell membranes
Step-by-step explanation:
The movement of the the fluid is a combination of both the osmotic and the hydrostatic pressures.
Osmotic pressure results from the differences in the solute concentrations across the cell membranes. On the other hand, hydrostatic pressure results from pressure of the blood as it enters the capillary system, forcing some amount of the fluid out of vessel into surrounding tissues.
As a result of these factors, the fluid movement occurs through cell membrane.