Question

The hydrostatic pressure that makes a diluted solution diffuse solvent molecules across a semipermeable membrane into a concentrated solution is known as

A. osmotic pressure.
B. ambient pressure.
C. absorption pressure.
D. adsorption pressure.

Answer 1

D i think,Vapor pressure lowering is a collective property because it has been found that when more moles of solute are added to solvent, it has lower's the solvent's vapor pressure(Raoult's Law).  

Answer 2

The correct answer to the statement above is letter A, osmotic pressure.

It is because the osmotic pressure is a kind of pressure where it is applied to a certain solution. It is being applied to a certain solution for the prevention of having it to flow in an inward motion which takes place across the semipermeable membrane.