The flow of solvent from pure solvent side to solution side across a semipermeable membrane can be stopped if some extra pressure is applied on the solution. This pressure that just stops the flow of solvent is called

Osmotic pressure of solution

The correct answer is Option (1) → Osmotic pressure of solution

Osmosis is the movement of solvent molecules through a semipermeable membrane from a region of pure solvent (or lower solute concentration) to a region of higher solute concentration (solution). If an external pressure is applied on the solution side, it can oppose the flow of solvent.

The minimum pressure required to stop the flow of solvent through the semipermeable membrane is called the osmotic pressure of the solution.