If $\overrightarrow a\times\overrightarrow b+\overrightarrow b\times\overrightarrow c+\overrightarrow c\times\overrightarrow a$ and $\overrightarrow a+\overrightarrow b+\overrightarrow c$ are $\perp$ then $\overrightarrow a,\:\overrightarrow b\:\overrightarrow c$ are .....

Question

$\begin{array}{1 1} \text{Coplanar} \\(B) \text{Mutually perpendicular} \\ (C) \text{Parallel to one another} \\ (D) \text{Do not lie in one plane}\end{array} $