Consider the following theorem: "Let f be a definite and continuous function in a closed interval (a, b) and derivable at the internal points. Then there is at least one point c , comprised between a and b , such that, f (b) - f (a ) = f '(c) (ba) ". How is this theorem known? Chain rule; Mean value Theorem; Rolle's Theorem; Extreme Value Theorem; None of above;