Simplify Assume That All Variables Represent Positive Real Numbers $\sqrt[3]{\frac{7}{9 x^{2}}}$

Multiple Choice

Simplify. Assume that all variables represent positive real numbers.
- $\sqrt[3]{\frac{7}{9 x^{2}}}$

A) $\frac{\sqrt[3]{21 x}}{3 x}$

B) $\frac{\sqrt[3]{567 x^{2}}}{9 x}$

C) $\frac{\sqrt[3]{567 x}}{81}$

D) $\frac{\sqrt[3]{63 x}}{9 x}$