The speed of sound in a gas is v and root mean square speed of gas molecules is ${\mathrm{V}}_{{\mathrm{rms}}^{\ast }}$ If the ratio of specific heats of the gas $\mathrm{\gamma }=1\cdot 5\text{, }$then the ratio $\mathrm{V}/{\mathrm{V}}_{\mathrm{rms}}$ is

• A

  1:2

• B

  2:1

• C

  $1:\sqrt{2}$

• D

  $\sqrt{2}:1$