Final answer:
Steel components such as cold drawn cables, rebar, and bolts begin to soften and lose strength at approximately 1200°F.
Step-by-step explanation:
The question pertains to the temperature at which certain steel components such as cold drawn cables, rebar, bolts, and extruded structural members like columns and beams begin to soften, elongate, and sag. Based on the provided options, steel often starts to soften and lose its mechanical strength at around 1200°F (approximately 649°C). However, specific temperatures might vary slightly depending on the composition and treatment of the steel. This softening is relevant to the behavior of steel in fires or high-temperature environments, where structural integrity is compromised due to the reduction in material stiffness and strength.