A capacitor is charged by a battery. The battery is removed and another identical uncharged capacitor is connected in parallel. The total electrostatic energy of resulting system :

Question

$\begin{array}{1 1} \text{(1) increases by a factor of 4} \\ \text{(2) decreases by a factor of 2} \\ \text{ (3) remains the same} \\ \text{(4) increases by a factor of 2} \end{array} $