The working principle of a washing machine is

Correct answer: (b) centrifugation

Explanation

A washing machine's spin-dry works on centrifugation, where rapid rotation creates centrifugal force that flings water out of wet clothes.

This force separates particles by density and mass, throwing heavier water outward through the drum holes.

Diffusion, dialysis and reverse osmosis are membrane/concentration-based processes, not used for spin drying.