Determine $( g \circ f ) ( x )$ For the Pair of Functions

Multiple Choice

Determine $( g \circ f ) ( x )$ for the pair of functions $f ( x ) = \sqrt { x + 8 } \text { and } g ( x ) = 9 x + 4$

A) $9 \sqrt { x + 8 } + 4$
B) $\sqrt { x + 8 }$
C) $9 ( x + 8 ) ^ { 2 } + 4$
D) $9 \sqrt { x - 8 } - 4$