Answer: C. temperature of the gas
Step-by-step explanation:
The kinetic theory says that the kinetic energy of the gas molecules (directly related to "how much" the molecules are moving inside the gas) is directly related to the internal energy of the gas, which is related to the temperature.
This relation can be written, in the kinetic theory, as:
(1/2)m*v^2 = (1/2)*Kb*T
where Kb is a constant, and the therm in the left is the kinetic energy, so here we can see that the kinetic energy is proportional to the temperature, where (1/2)*Kb is the constant of proportionality