How does resistance of a conductor vary with temperature?

An item or category of material that permits the movement of charge in one or more directions is referred to as a conductor. The obstruction to current flow in a wire or electrical circuit is measured by resistance. Resistance prevents electron flow when a potential difference is applied across a conductor, but the opposite is true for a potential difference.

Electric current is the movement or flow of particles that are electrically charged in a conductor. When an electric current passes through a conductor, free electrons wander across the metal. Electricity flows easily through a conductor because its electrons are free to move about. Every time an electron crosses a conductor, an electrical current is created.

Heat causes the atoms in a metallic conductor to vibrate more loudly and often. As the temperature rises, the thermal velocity of free electrons increases. This increases the conductor's resistance and, as a result, the barrier to electron mobility. As the temperature rises, the conductor's resistance rises due to an increase in internal collisions, which reduces the current flow.
As a result, the resistance of the wire rises with rising temperature and vice versa.

Hence, the correct answer is option A.