The work done in moving an object from origin to a point whose positiion vector is $\overrightarrow {r}=3 \hat {i}+ 2 \hat j-5 \hat k$ by a force $\overrightarrow {F}=2 \hat {i}- \hat j- \hat k$ is :

Question

$$(a)\;1\;unit \quad (b)\;9\;units \quad (c)\;13\;units \quad (d)\;60\;units$$