The ability of a material to resist deformation or deflection under stress is known as-

Explanation

Explanation: Stiffness Stiffness of a material is the resistance offered to deformation, below the elastic limit. A material with a high value of Young’s modulus E is stiffer than the material with the lower value of Young’s modulus. Small values of E indicate flexible materials and a large value of E reflects stiffness and rigidity. Toughness The ability of the material to withstand stress (resist fracture due to high impact loads) without fracture is known as toughness. It is defined as the ability to absorb energy in the plastic state. Ductility The property of the material that allows it to be drawn into wires or elongated before failure is known as ductility.