What effect does an increase in temperature have on electrical conductivity in metals?

The relationship between temperature and electrical conductivity in metals is generally characterized by an increase in conductivity with rising temperature. When temperature increases, the lattice structure of the metal vibrates more vigorously, which can create more opportunities for conduction. This increased thermal agitation causes the atoms to move, which can help free more electrons and facilitate their flow, ultimately enhancing electrical conductivity.

Thus, the correct answer is that an increase in temperature leads to an increase in electrical conductivity in metals. This phenomenon is rooted in the behavior of charge carriers (typically electrons) within the metal: as temperature rises, the increased kinetic energy allows for easier movement of these electrons, resulting in improved conductivity.

Other options suggest either no change or a decrease in conductivity or erratic behavior, which does not accurately reflect the typical conductive properties of metals as they experience increased temperature.