Which term refers to the capability of a material to withstand deformation and absorb energy before reaching failure?

The correct response is toughness. Toughness is defined as the ability of a material to absorb energy and deform plastically without fracturing. It is a crucial property in materials science because it indicates how well a material can withstand impacts or sudden forces without failing. Tough materials can absorb significant amounts of energy before reaching their failure point, which makes them ideal for applications where resistance to impact and stress is essential.

Elasticity refers to a material's ability to return to its original shape and size after being deformed, which is not necessarily related to the energy-absorbing capability before failure. Resilience is more specifically the ability of a material to absorb energy when it is deformed elastically and then return that energy upon unloading, thus it pertains to elastic deformation rather than overall toughness. Relaxation pertains to the reduction of stress in a material over time under constant strain and does not directly relate to the material's ability to absorb energy before failing.