The correct answer is: D. Both kinetic and potential energy.
When heat energy is supplied to a substance, it causes the molecules of the substance to move faster. This increase in molecular motion is what causes the temperature of the substance to increase. The faster-moving molecules have more kinetic energy.
In addition to the increase in kinetic energy, the heat energy also causes the molecules of the substance to vibrate more. This vibration is a form of potential energy.
Therefore, the supplied heat energy is stored in both kinetic and potential energy forms.
Option A is incorrect because heat energy is not stored in heat energy. Heat energy is a form of energy that is transferred from one object to another due to a difference in temperature.
Option B is incorrect because kinetic energy is not the only form of energy that is stored during a change in temperature. Potential energy is also stored during a change in temperature.
Option C is incorrect because potential energy is not the only form of energy that is stored during a change in temperature. Kinetic energy is also stored during a change in temperature.