Consider a mixture of gas molecules of types $A, B$,and $C$ having masses $m_{A} < m_{B} < m_{C}$. The ratio of their root mean square speeds at normal temperature and pressure is:

• A
  $v_{A} = v_{B} \neq v_{C}$
• B
  $\frac{1}{v_{A}} > \frac{1}{v_{B}} > \frac{1}{v_{C}}$
• C
  $v_{A} = v_{B} = v_{C} = 0$
• D
  $\frac{1}{v_{A}} < \frac{1}{v_{B}} < \frac{1}{v_{C}}$