Multiply, and Then Simplify If Possible $( 3 \sqrt { x } + 5 ) ( \sqrt { 3 x } - 5 )$

Multiple Choice

Multiply, and then simplify if possible. Assume all variables represent positive real numbers.
- $( 3 \sqrt { x } + 5 ) ( \sqrt { 3 x } - 5 )$

A) $3 x - 25$
B) $3 x - 30 \sqrt { x } - 25$
C) $3 x \sqrt { 3 } - 15 \sqrt { x } + 5 \sqrt { 3 x } - 25$
D) $3 x \sqrt { 3 } - 30 \sqrt { x } - 25$