Solve the Equation and Express the Solution in Exact Form $\ln x - \ln ( x - 4 ) = \ln 9$

Multiple Choice

Solve the equation and express the solution in exact form.
- $\ln x - \ln ( x - 4 ) = \ln 9$

A) $\varnothing$
B) $\{ 5 \}$
C) $\left\{ \frac { 9 } { 2 } \right\}$
D) $\left\{ \frac { 4 \ln 9 } { \ln 9 - 1 } \right\}$