Which of the following defines the ability of a material to return to its original shape when forces causing deformation are removed?

The ability of a material to return to its original shape after the forces that cause deformation are removed is defined as elasticity. This property is crucial in various engineering applications where materials must be subjected to stresses and then return to their initial configuration once those stresses are eliminated. Elasticity is characterized by a linear relationship between stress and strain within the elastic limit of the material, as described by Hooke's law.

In contrast, ductility refers to a material's ability to deform under tensile stress, typically measured by the extent of stretching before breaking, which does not necessarily involve returning to the original shape. Toughness signifies a material's ability to absorb energy and plastically deform without fracturing, and resilience measures the capacity to absorb energy when deformed elastically and then recover that energy upon unloading. While all these properties are significant in material science, elasticity specifically pertains to the recovery of original shape following deformation.