For yield strength, the units are typically on the order of $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.$ It is defined as $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.$

A MPa, ksi; the maximum stress on the engineering stress$-$strain curve

B MPa, ksi; a material's resistance to plastic deformation

C GPa, $10^3$ ksi; the maximum stress on the engineering stress$-$strain curve

D GPa, $10^3$ ksi; a material's resistance to plastic deformation