Four positive point chargers (+q) are kept at the four corners of a square of side 'l' . The net electric field at the midpoint of any one side of the square is , $ \bigg( take\: \large\frac{1}{4 \pi \varepsilon_{\circ}} = K \bigg)$

Question

$\begin {array} {1 1} (1)\;\large\frac{4Kq}{l^2} & \quad (2)\;\large\frac{16Kq}{5\sqrt 5.l^2} \\ (3)\;\large\frac{8Kq}{\sqrt 5.l^2} & \quad (4)\;\large\frac{Kq}{l^2} \end {array}$