Find a Formula for the Inverse Function $f^{-1}$ Of the Indicated Function

Find a formula for the inverse function $f^{-1}$ of the indicated function. $f(x) =2-x^{7}$

A) $f^{-1}(x) =(2-x) ^{\frac{1}{7}}$
B) $f^{-1}(x) =2-x^{\frac{1}{7}}$
C) $f^{-1}(x) =2+x^{\frac{1}{7}}$
D) $f^{-1}(x) =(2+x) ^{\frac{1}{7}}$