What does surface tension refer to?

Surface tension refers to the work required to increase the surface area of a liquid due to the cohesive forces acting within the liquid. At the surface of a liquid, molecules experience a different environment compared to those in the bulk, which leads to an imbalance of forces. This creates a ‘skin-like’ effect, causing the surface to behave like a stretched elastic membrane. Thus, increasing the surface area necessitates energy input to overcome these cohesive forces.

While cohesive forces contribute to surface tension, the question specifically addresses the work aspect, making the correct choice the definition that accurately captures the concept of surface tension in terms of energy and area.