the derivative of the twice-differentiable function f is shown below on th domain (-9,9). the graph of f priume has points inflection at x=-4, x=-1, x=3 indicate
a) f has local maxima at x=−4, x=−1, and x=3.
b) f has local minima at x=−4, x=−1, and x=3.
c) f changes concavity at x=−4, x=−1, and x=3.
d) f is discontinuous at x=−4, x=−1, and x=3.