Find the Domain of the Composite Function F $f ^ { \circ } g$

Multiple Choice

Find the domain of the composite function f $f ^ { \circ } g$
- $$f ( x ) = \frac { 1 } { x - 7 } ; \quad g ( x ) = \sqrt { x - 1 }$$

A) $\{ x \mid x \geq 1 , x \neq 7 \}$
B) $\{ x \mid x \geq 1 , x \neq 7 , x \neq 50 \}$
C) $\{ x \mid x$ is any real number $\}$
D) $\{ x \mid x \geq 1 , x \neq 50 \}$