Find a Unit Vector in the Direction of the Given $\left[ \begin{array} { r } - 4 \\ 4 \\ - 2 \end{array} \right]$

Find a unit vector in the direction of the given vector.
- $\left[ \begin{array} { r } - 4 \\ 4 \\ - 2 \end{array} \right]$

A)
$\left[ \begin{array} { r } - \frac { 2 } { 3 } \\ \frac { 2 } { 3 } \\ - \frac { 1 } { 3 } \end{array} \right]$

B)

$\left[ \begin{array} { l } \frac { 2 } { 3 } \\ \frac { 2 } { 3 } \\ \frac { 1 } { 3 } \end{array} \right]$
C)
$\left[\begin{array}{c}-\frac{2}{\sqrt{5}} \\\frac{2}{\sqrt{5}} \\-\frac{1}{\sqrt{5}}\end{array}\right]$

D)
$\left[\begin{array}{r}-\frac{2}{9} \\\frac{2}{9} \\-\frac{1}{9}\end{array}\right]$