What is the principle of purification by soap?

The principle of purification by soap is based on surface tension; option [A]. Soap molecules contain both hydrophilic and hydrophobic parts. When soap is added to water, its hydrophobic tails attach to oil and grease, while the hydrophilic heads face outward. This forms structures called micelles, which encapsulate the dirt and oil, breaking them into smaller droplets suspended in the water. These micelles reduce the surface tension of water, allowing the trapped particles to be easily lifted away. This mechanism is essential for cleaning surfaces as it prevents the redeposition of dirt and oil onto cleaned surfaces. Therefore, the effectiveness of soap in purification is fundamentally tied to its ability to alter surface tension, facilitating the removal of contaminants and ensuring thorough cleaning across various surfaces.