Circular disc X of radius R is made from an iron plate of thickness t, and another disc Y of radius 4 R is made from an iron plate of thickness.$\frac{\mathrm{t}}{4}$.Then, the relation between the moment of inertia I_X, and Iy is

• A

  ${\mathrm{I}}_{\mathrm{Y}}=64{\mathrm{I}}_{\mathrm{X}}$

• B

  ${\mathrm{I}}_{\mathrm{Y}}=32{\mathrm{I}}_{\mathrm{X}}$

• C

  ${\mathrm{I}}_{\mathrm{Y}}=16{\mathrm{I}}_{\mathrm{X}}$

• D

  $\mathrm{I}={\mathrm{I}}_{\mathrm{X}}$