Which of the following best describes toughness in material science?

Toughness in material science is best described as the ability of a material to absorb energy and undergo plastic deformation without experiencing rupture. This characteristic indicates that a tough material can withstand significant stress and strain, making it highly desirable in applications where materials are subject to impact and dynamic loading.

Toughness relates to not just the strength of a material under tension but also its ability to deform without failing. It plays a crucial role in assessing how materials will behave under real-world conditions, such as in construction, automotive, and aerospace industries, where materials must endure varying loads.

The other options reflect different properties of materials, such as hardness (resistance to indentation) and elasticity (ability to return to original shape post-deformation), but they do not encompass the complete scope of toughness as it pertains to energy absorption and plasticity before rupture. The concept of breaking under low impact suggests a brittle characteristic, which is the opposite of toughness, highlighting why the first option is the most accurate description.