If the Function Is One-To-One, Find Its Inverse $$f ( x ) = \sqrt { x - 7 } , x \geq 7$$

Multiple Choice

If the function is one-to-one, find its inverse. If not, write "not one-to-one."
- $$f ( x ) = \sqrt { x - 7 } , x \geq 7$$

A) $f ^ { - 1 } ( x ) = ( x - 7 ) ^ { 2 }$
B) not a one-to-one
C) $\mathrm { f } ^ { - 1 } ( \mathrm { x } ) = \mathrm { x } ^ { 2 } + 7 , \mathrm { x } \geq 0$
D) $f ^ { - 1 } ( x ) = \sqrt { x + 7 }$