Find the values of x that are critical numbers of the function f (x) = 3x4 - 16x3 + 6x2 +723 +1. O A. * = -3, = -2, and * = -1 O B. x = -3, x = -2, and x = 1 O C. x= -3, x = 2, and x = 3 O D. = -1, x = 2, and X = 3 O E. x = 1, X = 2, and x = 3