The skin effect of a conductor will reduce as the

Resistivity of conductor material increases
Permeability of conductor material increases
Diameter increases
Frequency increases

The correct answer is: The skin effect of a conductor will reduce as the diameter increases.

Skin effect is the tendency of an alternating electric current (AC) to flow predominantly near the surface of a conductor, rather than through the entire cross-section of the conductor. This is due to the fact that the resistance of a conductor is inversely proportional to the square of the conductor’s radius. As the frequency of the AC current increases, the skin depth decreases, meaning that the current flows in an increasingly thinner layer near the surface of the conductor.

The resistivity of a conductor is a measure of its resistance to the flow of an electric current. The higher the resistivity, the greater the resistance to the flow of current. However, the skin effect is not affected by the resistivity of the conductor.

The permeability of a conductor is a measure of its ability to be magnetized. The higher the permeability, the greater the ability to be magnetized. However, the skin effect is not affected by the permeability of the conductor.

The diameter of a conductor is a measure of its cross-sectional area. The larger the diameter, the greater the cross-sectional area. The skin effect is inversely proportional to the square of the conductor’s radius, so the larger the diameter, the smaller the skin depth and the less the current will flow near the surface of the conductor.

Therefore, the skin effect of a conductor will reduce as the diameter increases.