$\begin{array}{1 1} (A)\;\frac{8^x}{x^8}[\log 8+\frac{8}{x}] \\ (B)\;\frac{8^x}{x^8}[x\log 8+\frac{8}{x}] \\ (C)\;\frac{8^x}{x^8}[\log 8-\frac{8}{x}] \\ (D)\;\frac{8^x}{x^8}[x\log 8-\frac{8}{x}] \end{array} $