c
As we know, moment of inertia of a disc about an axis passing through \(C.G.\) and perpendicular to its plane, \({I_z}\, = \frac{{m{R^2}}}{2}\) Moment of inertia of a disc about a tangential axis perpendicular to its own plane, \({I_z}'\, = \frac{3}{{20}}m{R^2}\) \({I_z}/{I_z}'\, = \frac{{m{R^2}}}{2}/\frac{{3m{R^2}}}{2}\, = 1/3\)
