The Largest Set on Which $f ( x ) = \sqrt { x + 4 }$

Multiple Choice

The largest set on which $f ( x ) = \sqrt { x + 4 }$ is continuous is

A) $( - \infty , \infty )$
B) $( - 4 , \infty )$
C) $( 4 , \infty )$
D) $[ - 4 , \infty )$
E) $[ 4 , \infty )$