The displacement of a charge $Q$ in the electric field $E^{-}=e_{1} i \wedge+e_{2} j \wedge+e_{3} k \wedge$ is $r^{-}=a i \wedge+b j \wedge$
The work done is $\ldots \ldots$
(A) $Q\left(e_{1}+e_{2}\right) \sqrt{\left(a^{2}+b^{2}\right)}$
(B) $Q\left[\sqrt{ \left.\left(e_{1}^{2}+e_{2}^{2}\right)\right](a+b)}\right.$
(C) $Q\left(a e_{1}+b e_{2}\right)$
(D) $\left.Q \sqrt{[}\left(a e_{1}\right)^{2}+\left(b e_{2}\right)^{2}\right]$