In a parallel plate capacitor, the capacity increases, if      

In a parallel plate capacitor, the capacity of capacitor,

                     $\mathrm{C}=\frac{{\mathrm{K\epsilon }}_0\mathrm{A}}{\mathrm{d}}$

$\therefore$                 $\mathrm{C}\propto \mathrm{A}$

So, the capacity of capacitor increases, if area of the plate is increased.