The net resistance between the points A and B is

$\begin {array} {1 1} (A)\;\large\frac{R}{2} & \quad (B)\;\large\frac{2R}{5} \\ (C)\;\large\frac{5R}{2} & \quad (D)\;\large\frac{3R}{2} \end {array}$

The question as given might seem tricky to approach but a simple connection
of the two grounds would lead to a circuit which might seem familiar.
Ans : (C)
edited Sep 11, 2014 by meena.p