Rewrite the Radical Expression Using Rational Exponents $(\sqrt[9]{b})^{7}$ A) $b^{7 / 9}$

Multiple Choice

Rewrite the radical expression using rational exponents. A ssume all variables represent nonnegative real numbers.
- $(\sqrt[9]{b}) ^{7}$

A) $b^{7 / 9}$
B) $b^{-9 / 7}$
C) $b^{-7 / 9}$
D) $b^{9 / 7}$