Which of the following limits represent a derivative of the function f(x) = x³?

(ath)3 - 23 lim h-+0 h 1 lim h-+0 (xth)3 - x3 lim (3x2 + 3ch + h2 - 1) h-+0 3x2 - 1 lim h-+0 h lim (3x + 3xh + h-) h-+0