Rewrite the Ratio as a Ratio of Natural Logarithms and Simplify

Multiple Choice

Rewrite the ratio as a ratio of natural logarithms and simplify.
- $\frac { \log _ { 243 } x } { \log 3 x }$

A) $\frac { 1 } { 5 }$
B) $3 ^ { 4 }$
C) $\ln 5$
D) $\frac { 1 } { 3 ^ { 4 } }$