A parallel plate condenser with oil between the plates (dielectric constant of oil $K=2$) has a capacitance $C$. If the oil is removed, the capacitance of the capacitor becomes :

Question

( A ) $2C$
( B ) $\frac{C}{\sqrt{2}}$
( C ) $\sqrt{2}C$
( D ) $\frac{C}{2}$