What is the key difference between elastic and plastic deformation in a material?
Elastic deformation is reversible, meaning the material returns to its original shape after the load is removed, while plastic deformation results in permanent changes. As per NCERT, applying relevant law/formula with correct units and sign convention leads to Elastic deformation is reversible, plastic is not. This satisfies dimensional consistency and physical conditions given, so option D is scientifically correct.
Ref: NCERT Class 11 Physics, Thermal Properties and Gravitation.