Find $f^{\text{'}}(x)$ and find the value$($s$)$ of $x$ where the tangent line is horizontal.

$f(x)=\frac{x}{(7x-6{)}^8}$

$f^{\text{'}}(x)=-\frac{49x+6}{(7x-6{)}^9}$

Select the correct choice below and fill in any answer boxes in your choice

A$.$ The value$($s$)$ of $x$ where the tangent line is horizontal is $($Use a comma to separate answers as needed.$)$

B$.$ The tangent line is never horizontal.