What is temperature a measure of in a substance?

Temperature is a measure of the average kinetic energy of the particles in a substance. This means that it reflects how fast the particles are moving; as the speed of these particles increases, the temperature of the substance rises. In essence, temperature indicates the energy associated with the motion of atoms and molecules within that material.

The other options describe related concepts but do not accurately define what temperature itself measures. For instance, while the amount of energy required to change temperature is related to specific heat capacity, it does not define temperature itself. Similarly, the lowest point of thermal energy pertains to absolute zero but is not an expression of temperature as a measure. Finally, total heat energy accounts for both temperature and the mass of the substance but does not represent the average energy of the individual particles, which is what temperature specifically gauges.