To solve the inequality \( x - 5 < \frac{x}{6} \), the first step should be to eliminate the fraction for easier comparison.
The correct choice is:
D. Multiply both sides of the inequality by 6 to simplify: \( 6(x - 5) < x \)
This simplifies to:
\[ 6x - 30 < x \]
So, option D is the appropriate first step in solving the inequality.