Which materials exhibit little or no yielding before they fail?

The correct choice is brittle materials, which are characterized by their tendency to fail suddenly and without significant prior deformation or yielding. When subjected to stress, brittle materials do not undergo substantial plastic deformation; instead, they break or fracture once they reach their ultimate strength. This behavior is often seen in materials such as glass, ceramics, and certain types of metals when they are in a hardened state.

In contrast, ductile materials are known for their ability to deform significantly before failing. They can experience noticeable elongation and redistribution of areas under stress, allowing them to absorb energy and undergo plastic deformation. Malleable materials, similarly, can be shaped and deformed without breaking, and they too exhibit considerable yielding. Plastic materials generally undergo both elastic and plastic deformation, allowing for more considerable shape changes before failure.

Thus, the distinction lies in the nature of how each type of material responds to applied stress, with brittle materials being the ones that exhibit little or no yielding before failing.