Evaluate the Following Expression $5 \cos 5 x - \frac { 5 \cos 5 x } { 1 - \tan 5 x }$

Multiple Choice

Evaluate the following expression.(x ? ?/10 + ?n,where n is a whole number) ? $5 \cos 5 x - \frac { 5 \cos 5 x } { 1 - \tan 5 x }$ ?

A) $\frac { 10 \sin 5 x \cos 5 x } { \sin 5 x - \cos 5 x }$
B) $\frac { - 5 \sin 5 x \cos 5 x } { \sin 5 x + \cos 5 x }$
C) $\frac { 5 \sin 5 x \cos 5 x } { \sin 5 x - \cos 5 x }$
D) $\frac { - 5 \sin 5 x \cos 5 x } { \sin 5 x - \cos 5 x }$
E) $\frac { 5 \sin 5 x \cos 5 x } { \sin 5 x + \cos 5 x }$