Evaluate the Function $r ( x ) = \frac { 3 } { x - 4 }$

Multiple Choice

Evaluate the function.
-If $r ( x ) = \frac { 3 } { x - 4 }$ , find $r ( a + 5 )$

A) $- \frac { 3 } { 4 } a - \frac { 15 } { 4 }$
B) $\frac { 3 } { a - 4 } + 3$
C) $\frac { 8 } { a - 4 }$
D) $\frac { 3 } { a + 1 }$