Find the Length of the Curve $\mathbf { r } ( t ) = - 2 t \mathbf { i } - t \mathbf { j } + t \mathbf { k } , - 2 \leq t \leq 1$

Multiple Choice

Find the length of the curve $\mathbf { r } ( t ) = - 2 t \mathbf { i } - t \mathbf { j } + t \mathbf { k } , - 2 \leq t \leq 1$ .

A) $3 \sqrt { 6 }$
B) $\sqrt { 6 }$
C) $2 \sqrt { 6 }$
D) $6 \sqrt { 6 }$