Suppose f(x) is a function with the following properties: f^{\prime \prime}(1)=f^{\prime \prime}(2)=f^{\prime \prime}(4)=0 \text { - } f^{\prime \prime}(x)>0 \text { for all } x \text { on }(-\infty, 1)

\cup(4, \infty) \text {, and } \text { - } f^{\prime \prime}(x)<0 \text { for all } x \text { on }(1,2) \cup(2,4) \text {. } Which of the following is always TRUE? Of has exactly two inflection points which occur at x = 1 and x = 2. f has exactly two inflection points which occur at x = 1 and x = 4. Of does not have any inflection points. Of has exactly three inflection points which occur at x = 1, x = 2, and x = 4. Of has exactly two inflection points which occur at x = 2 and x = 4.