Answer the following question given this paragraph: 

Iron is oxidized to Fe2+(aq) at an anodic site on the surface of the iron, which is often an impurity or a lattice defect. Oxygen is reduced to water at a different site on the surface of the iron, which acts as the cathode. Electrons are transferred from the anode to the cathode through the electrically conductive metal. Water is a solvent for the Fe2+ that is produced initially and acts as a salt bridge. Rust (Fe2O3·xH2O) is formed by the subsequent oxidation of Fe2+ by atmospheric oxygen. In the corrosion process, iron metal acts as the anode in a galvanic cell and is oxidized to Fe2+; oxygen is reduced to water at the cathode. The relevant reactions are as follows:.


Q: Iron is oxidized to fe2+(aq) at an anodic site on the surface of the iron, which is often an impurity or this?

 Choices:

- displacement defect

- spontaneous mutation

- ladder complex

- lattice defect

A:
lattice defect
