The moment of inertia of a thin uniform circular disc about one of the diameters is I. Its moment of inertia about an axis perpendicular to the plane of the disc and passing through its centre is

• A

  $\left(\sqrt{2}\right)\mathrm{I}$

• B

  2I

• C

  I/2

• D

  $\frac{\mathrm{I}}{\sqrt{2}}$