What happens to the kinetic energy of an object as its temperature rises?

As the temperature of an object rises, the kinetic energy of its particles increases. This is because temperature is a measure of the average kinetic energy of the particles in a substance. When thermal energy is added, whether through heating or other means, the particles move more vigorously, which corresponds to an increase in their kinetic energy.

This increase can be observed in various states of matter—solids, liquids, and gases. In solids, the atoms vibrate more rapidly around their fixed positions as temperature rises. In liquids, the particles move more freely and energetically, and in gases, the distance between particles increases along with their speed. Thus, a rise in temperature leads directly to a rise in kinetic energy, which is why this choice is the correct answer.