Determine Whether the Given Function Is One-To-One $$f ( x ) = \frac { 4 } { x + 5 }$$

Multiple Choice

Determine whether the given function is one-to-one. If so, find a formula for the inverse.
- $$f ( x ) = \frac { 4 } { x + 5 }$$

A) $f ^ { - 1 } ( x ) = \frac { - 5 x + 4 } { x }$
B) $f ^ { - 1 } ( x ) = \frac { 5 + 4 x } { x }$
C) Not a one-to-one function
D) $f ^ { - 1 } ( x ) = \frac { x } { 5 + 4 x }$