If the rms speed of the molecules of a gas at a temperature of $77^{\circ} \mathrm{C}$ is $50 \mathrm{~ms}^{-1}$, then the rms speed of the same gas molecules at a temperature of $150.5^{\circ} \mathrm{C}$ is

• A

  $65 \mathrm{~ms}^{-1}$
• B

  $35 \mathrm{~ms}^{-1}$
• Correct answer
  C

  $55 \mathrm{~ms}^{-1}$
• D

  $45 \mathrm{~ms}^{-1}$

Hence, the correct answer is option: 'C'.