Rewrite Without Rational Exponents, and Simplify, If Possible $(16 x)^{7 / 2}$

Multiple Choice

Rewrite without rational exponents, and simplify, if possible.
- $(16 x) ^{7 / 2}$

A) $16,384 \sqrt{x^{14}}$
B) $2 \sqrt{8 x}$
C) $128 \sqrt{x}$
D) $16,384 x^{3} \sqrt{x}$