Which of the following is the most elastic material?

This question probes the concept of elasticity in material science. In physics, elasticity refers to a material's ability to return to its original shape after deformation, and its resistance to permanent change. A material is considered more elastic if it has a higher Young's modulus, meaning it requires more force to deform it and returns more precisely. Steel is highly elastic because it can withstand significant stress and return to its exact original shape, storing and releasing substantial elastic energy.

• Rubber is flexible but deforms easily and has a lower Young's modulus, not returning as perfectly under high stress.
• Sponge is compressible but not truly elastic in the sense of resisting deformation.
• Glass is brittle and fractures with minimal elastic deformation.