Two infinitely long line of charge carrying charges $+\lambda \left(\raisebox{1ex}{$C$}\!\left/ \!\raisebox{-1ex}{$m$}\right.\right)$  and  $-\lambda \left(\raisebox{1ex}{$C$}\!\left/ \!\raisebox{-1ex}{$m$}\right.\right)$are kept at a separation $r$. Then the electric field at a distance $r$ from each line of charge is 

• A

  $\frac{2\sqrt{2}\lambda }{\pi {\in }_{0}r}$

• B

  $\frac{\lambda }{\pi {\in }_{0}r}$

• C

  $\frac{\lambda }{2\pi {\in }_{0}r}$

• D

  $\lambda /\sqrt{2}\pi {\in }_{0}r$