Which of the following best describes a conductor?

A conductor is defined as a material that allows the flow of electric charge or heat. Option C accurately describes a conductor as a material that conducts heat well. In conductors, such as metals, the electrons are free to move, enabling them to transfer energy efficiently. This property is crucial in various applications, including electrical wiring and thermal management, where efficient energy transfer is desired.

The other options do not correctly characterize a conductor. For example, a material that absorbs heat might be an insulator, which does not allow for efficient energy transfer. Additionally, materials that do not conduct electricity would also be classified as insulators, not conductors. Finally, a material described as resistant to heat does not align with the properties of a conductor, as it implies a function of insulating against heat rather than conducting it. Therefore, option C is the most accurate description of a conductor in both thermal and electrical contexts.