<prompt> Most impoant factor for maintaining intravascular fluid volume -Hydrostatic pressure in capillariesOsmotic pressure in capillariesHydrostatic pressure in interstitial spaceOsmotic pressure in interstitial space  <response>: Ans. is b i.e., Osmotic pressure in capillariesRef: Understanding medical physiology p. 331Hydrostatic pressure in the capillaries, i.e., capillary blood pressure creates an outward driving force i.e., tries to force the fluid from the capillary to interstitial space.Osmotic pressure in the capillaries creates an inward driving force, ie., tries to keep the fluid in the capillary. 