During an adiabatic process, the pressure of a gasis found to be proportional to the cube of its temperature.The ratio of $$\frac{C_{p}}{C_{v}}$$.The ratio of $$\frac{C_{p}}{C_{v}}$$ of the gas is

A

$$\frac{3}{2}$$

B

$$\frac{4}{3}$$

C

2

D

$$\frac{5}{3}$$