Two straight long conductors AOB and COD are perpendicular to each other and carry currents I₁ and I₂. The magnitude of the magnetic induction at a point P at a distance d from the point O in a direction perpendicular to the plane ABCD is

• A

  $\frac{{\mathrm{\mu }}_0}{2\mathrm{\pi d}}\left({\mathrm{I}}_1+{\mathrm{I}}_2\right)$

• B

  $\frac{{\mathrm{\mu }}_0}{4\mathrm{\pi d}}\left({\mathrm{I}}_1+{\mathrm{I}}_2\right)$

• C

  $\frac{{\mathrm{\mu }}_0}{2\mathrm{\pi d}}\sqrt{{\mathrm{I}}_1^2+{\mathrm{I}}_2^2}$

• D

  $\frac{{\mathrm{\mu }}_0}{2\mathrm{\pi d}}\left(\frac{{\mathrm{I}}_1{\mathrm{I}}_2}{{\mathrm{I}}_1+{\mathrm{I}}_2}\right)$