For the Given Functions F and G, Find the Composition $$f ( x ) = x ^ { 2 } + 3 x ; g ( x ) = \sqrt { x }$$

For the given functions f and g, find the composition.
- $$f ( x ) = x ^ { 2 } + 3 x ; g ( x ) = \sqrt { x }$$
Find $( g \circ f ) ( 0 )$ .

A) 0
B) 3
C) $\sqrt { 3 }$
D) $2 \sqrt { 3 }$