Consider the graph of the derivative of f() shown below: y = f'(x) -3 -2 -1 0 1 2 3 Which one of the following statements about f (r) is true? The function f(a) has a local minimum at = = -2. The function f(z) is concave down on the interval (-1, 3). The function f(a) has a local maximum at x = -1. The function f() is concave down for all = > 1