What is the inverse of f(x) = (x+6)² for x ≥ -6 where function g is the inverse of function f?
a. g(x) = x+6−−−−√, x≥−6
b. g(x) = x−6−−−−√, x≥6
c. g(x) = x√−6, x≥0
d. g(x) = x√+6, x≥0