Pour electric charges \[+q,+q,-q\] and \[-q\] are placed at the comers of a square of side 2L (see figure). The electric potential at point A, mid-way between the two charges \[+q\] and \[+q,\] is [AIPMT (S) 2011]

• A. \[\frac{1}{4\pi {{\varepsilon }_{0}}}\frac{2q}{L}\left( 1+\frac{1}{\sqrt{5}} \right)\]
• B. \[\frac{1}{4\pi {{\varepsilon }_{0}}}\frac{2q}{L}\left( 1-\frac{1}{\sqrt{5}} \right)\]
• C. zero      
• D. \[\frac{1}{4\pi {{\varepsilon }_{0}}}\frac{2q}{L}\left( 1+\sqrt{5} \right)\]