Simplify the Expression $\sqrt { 64 x } + \sqrt { 9 x }$

Multiple Choice

Simplify the expression $\sqrt { 64 x } + \sqrt { 9 x }$ .

A) $\sqrt { x }$
B) 67 $\sqrt { x }$
C) 11x
D) 11 $\sqrt { x }$
E) $\sqrt { 11 }$ x