What happens if you increase the cross section of a conductor?

Increasing the cross section of a conductor primarily affects its resistance. The resistance of a conductor is inversely proportional to its cross-sectional area; that is, as the area increases, the resistance decreases. This phenomenon occurs because a larger cross section allows more electrons to flow through the conductor simultaneously, facilitating better current conduction.

In practical terms, when you have a thicker conductor, it can carry more current with less resistance, resulting in lower energy losses due to heat (which occurs when resistance is present). This principle is essential in electrical engineering and applications where efficient current flow is crucial. Thus, the choice that mentions the change in resistance due to the increased cross section is clearly the correct answer.