(a) Explain the meaning of f[f(x)]. (b) Find f[f(x)] for f(x) =2x". (a) Choose the correct interpretation below. O A. f[f(x)] means "the inverse of the function of x" O B. f[f(x)] means "the function of the function of x" O C. f[f(x)] means "the function of x times (" O D. f[f(x)] means "the function of x times the function of x" (b) f[f(x)] = (Simplify your answer.)