What core material property determines the inductance of an inductor?

Permeability is the measure of a material's ability to support the formation of a magnetic field within itself. In the context of an inductor, a core with higher permeability concentrates the magnetic lines of flux more effectively, thereby increasing the total inductance for a given number of turns. Distractors like permittivity apply to electric fields and capacitors, not magnetic fields and inductors. Resistance and reactivity relate to the overall circuit opposition to current, not the intrinsic physical property of the core that dictates its magnetic strength.