If $\overrightarrow{a}=\hat i-\hat j+2\hat k\;and\;\overrightarrow{b}=2\hat i-\hat j-2\hat k,$then find the unit vector in the direction of $ 6 \overrightarrow{b} $

Question

$\begin{array}{1 1} (A)\;\large\frac{1}{\sqrt 3}(2 \hat {i}- \hat {j}-2 \hat {k}) \\ (B)\;(2 \hat {i}- \hat {j}-2 \hat {k}) \\(C)\;\large\frac{1}{3}(2 \hat {i}- \hat {j}-2 \hat {k}) \\ (D)\;\large\frac{1}{3}(2 \hat {i}+ \hat {j}+2 \hat {k}) \end{array} $