The absolute temperature of a perfect gas is proportional to the average
Answer Details
The absolute temperature of a perfect gas is proportional to the average kinetic energy of the molecules. This means that as the temperature of the gas increases, the average kinetic energy of its molecules also increases, and vice versa. The temperature of a gas is a measure of the average kinetic energy of its particles, where the higher the temperature, the more kinetic energy the particles have. Therefore, the option that correctly completes the sentence is "kinetic energy of the molecules".