According to kinetic theory of gases,

A.  The motion of the gas molecules freezes at $0{}^{0}C$

B. the mean free path of gas molecules decreases if the density of molecules is increased.

C. the mean free path gas molecules increase if temperature is increased keeping pressure constant
D. average kinetic energy per molecules per degree of freedom is $\frac{3}{2}{k}_{B}T$ (for monatomic gases)

Choose the most appropriate answer from the options given below: