Which method would NOT effectively conduct thermal energy?

The method that would not effectively conduct thermal energy is indeed the use of a non-metallic insulator. Non-metallic insulators are materials that do not allow heat to pass through them easily. This is due to their atomic structure, which does not facilitate the transfer of kinetic energy between particles, meaning that they do not readily allow the conduction of heat.

In contrast, metal conductors are excellent at transferring thermal energy because their atomic structure allows for the free movement of electrons, which can carry heat efficiently. Similarly, using a liquid to transfer heat can be effective, particularly in cases like convection currents in water, where heated liquid rises and cool liquid sinks, distributing thermal energy. Direct contact between objects also promotes heat transfer through conduction, as thermal energy moves from the hotter object to the cooler one via direct particle interactions.

Thus, a non-metallic insulator is characterized by its low thermal conductivity, making it the least effective method for conducting thermal energy among the options presented.