直线(x)/(3)=(y-2)/(4)=(z-5)/(-1)与直线{2x+2y-z=-23, 3x+8y+z=18.之间的夹角为(）.A. (pi)/(4)B. (pi)/(6)C. (pi)/(3)D. (pi)/(2)

直线$\frac{x}{3}=\frac{y-2}{4}=\frac{z-5}{-1}$与直线$\left\{\begin{array}{l}2x+2y-z=-23, \\ 3x+8y+z=18\end{array}\right.$之间的夹角为(）.

A. $\frac{\pi}{4}$

B. $\frac{\pi}{6}$

C. $\frac{\pi}{3}$

D. $\frac{\pi}{2}$