# Any three vectors such that $\overrightarrow{a}. \overrightarrow{b} \neq 0,\;\overrightarrow{b}. \overrightarrow{c} \neq 0$, then $\overrightarrow{a}$ and $\overrightarrow{c}$ are :
( C ) inclined at an angle of $\frac{\pi}{6}$ between them
( D ) inclined at an angle of $\frac{\pi}{3}$ between them