Which of the following defects is observed in steel?

Step-by-step solution

Steel is an alloy composed primarily of iron and a small amount of carbon. In the crystal lattice of iron, the much smaller carbon atoms occupy the interstitial voids between the iron atoms. When foreign atoms occupy the interstitial sites of a host lattice, the defect is known as an interstitial impurity defect. Therefore, steel exhibits an interstitial impurity defect. Answer: Interstitial impurity defect