A ray of light incidents at an angle of $60^{\circ}$ on the first face of a prism. The angle of the prism is $30^{\circ}$ and its second face is silvered. If the light ray inside the prism retraces its path after reflection from the second face, then the refractive index of the material of the prism is

• A

  $\frac{2}{\sqrt{3}}$
• B

  $\frac{3}{2}$
• C

  $\sqrt{2}$
• Correct answer
  D

  $\sqrt{3}$

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