A function value f(a) is called a relative minimum of f if there exists:
A) An interval (x1, x2) that contains a such that x1 < x < x2 implies f(a) less than or equal to f(x).
B) An interval (x1, x2) that contains a such that x1 < x < x2 implies f(a) greater than or equal to f(x).
C) An interval (x1, x2) that contains a such that x1 > x > x2 implies f(a) less than or equal to f(x).
D) An interval (x1, x2) that contains a such that x1 > x > x2 implies f(a) greater than or equal to f(x).