The displacement $r$ of a charge $Q$ in an electric field $\overrightarrow{E} = c_1 \hat{i} + c_2 \hat{j} + c_3 \hat{k}$ is $\overrightarrow{r} = a \hat{i} + b \hat{j}$. The work done is :

Question

( A ) $Q (a c_1 + b c_2)$
( B ) $Q\sqrt{ (a c_1)^2 +( b c_2)^2 }$
( C ) $Q ( c_1 + c_2) \sqrt{a^2 + b^2}$
( D ) $Q (\sqrt{c_2^2 + c_1^2)} (a+b)$