The potential at a point x (measured in $\mathrm{\mu }$m) due to some charges situated on the X-axis is given by $\mathrm{V}\left(\mathrm{x}\right)=20/\left({\mathrm{x}}^2-4\right)$ volt. The electric field E at x = 4 $\mathrm{\mu }$m is given by

• A

  10/9 volt/$\mathrm{\mu }$m and in the - ve X direction

• B

  10i9 volt/$\mathrm{\mu }$m and in the +ve X direction

• C

  5/3 volt/$\mathrm{\mu }$m and in the - ve X direction

• D

  5/3 volt/$\mathrm{\mu }$m and in the +ve X direction