Express the Given Function as a Composite of Functions F $f ( x ) = \sqrt { x - 5 }$

Multiple Choice

Express the given function as a composite of functions f and g such that y = f(g(x) ) .
-Let $f ( x ) = \sqrt { x - 5 }$ . Find a function $y = g ( x )$ so that $( f \circ g ) ( x ) = \sqrt { x ^ { 2 } - 5 }$ .

A) $g ( x ) = x ^ { 2 } + 5$
B) $g ( x ) = 2 x$
C) $g ( x ) = x ^ { 2 }$
D) $g ( x ) = x ^ { 2 } - 5$