The correct mechanism by which scent spreads all over the room when the lid of a bottle is opened is through diffusion. Diffusion is the process by which molecules move from an area of high concentration to an area of low concentration. In the case of scent, when the lid is opened, the molecules of the scent begin to move from the area of high concentration inside the bottle to the area of low concentration in the room. This movement is driven by the natural tendency of molecules to distribute evenly throughout a space.

Option 1, pressure in the bottle, is not the correct mechanism for scent spreading. While there may be some increase in pressure when the lid is opened, it is not the driving force behind the scent spreading throughout the room.

Option 2, compression from the bottle, is also not the correct mechanism. Compression refers to the reduction in volume or increase in pressure due to external forces, but it does not explain the spreading of scent molecules in the air.

Option 4, osmosis, is not the correct mechanism either. Osmosis is the movement of solvent molecules across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration. It is not the relevant process for scent spreading.

In conclusion, the