Answer
The resistivity of a metallic conductor increases with increasing temperature.
Work Step by Step
In a metallic conductor, the current is carried by free electrons in the conductor which flow in the electric field. As the temperature increases, the electrons which are bound in atoms vibrate more rapidly, thus causing more collisions with the flowing free electrons. Since the free electrons experience more collisions, it is harder for them to flow through the material, which means that the resistivity of the material has increased.
Therefore, the resistivity of a metallic conductor increases with increasing temperature.
