All of the given choices are polynomials. If the graph of a polynomial function f in the xy-plane has an x-intercept at b, then (x−b) must be a factor of f(x). Since −3,−1, and 1 are each x-intercepts of the graph of f, it follows that (x+3),(x+1), and (x−1) must each be a factor of f(x).The factored polynomial function in choice C is the only polynomial given with these 3 factors. Choices A, B, and D are incorrect because they do not contain all three factorsthat must exist if the graph of the polynomial function f has x-intercepts at −3,−1, and 1.