18. The number of distinct roots of\\
$\left| \begin{array} { l } \sin x \cos x \cos x \\ \cos x \sin x \cos x \\ \cos x \cos x \sin x \end{array} \right| = 0$ in the interval $- \frac { \pi } { 4 } \leq x \leq \frac { \pi } { 4 }$ is:\\
(A) 0\\
(B) 2\\
(C) 1\\
(D) 3\\