Answer:
The average kinetic energy of the molecules in the system
Step-by-step explanation:
According to the kinetic theory of matter, the particles of a system are in constant motion and collide steadily with one another as well as with the walls of the container.
The average kinetic energy of these molecules in motion is referred to as the temperature of the body. Hence, temperature is a measure of the average kinetic energy of the molecules of a body.