Let $f ( x ) = 5 ^ { \cot ( 3 x ) }$

Multiple Choice

Let $f ( x ) = 5 ^ { \cot ( 3 x ) }$ Then $f ^ { \prime } ( x )$ is

A) $15 ^ { \csc ^ { 2 } ( 3 x ) }$
B) $- 15 ^ { \csc ^ { 2 } ( 3 x ) }$
C) $15 ^ { \cot ( 3 x ) } \left( \csc ^ { 2 } ( 3 x ) \right)$
D) $5 ^ { \cos ( 3 x ) } \left( 3 \csc ^ { 2 } ( 3 x ) \right)$
E) $- 5 ^ { \cos ( 3 x ) } \left( 3 \csc ^ { 2 } ( 3 x ) \ln 5 \right)$