The function $f$ has a continuous second derivative, and it satisfies $f(9) = -6$, $f'(9) = 0$ and $f''(9) = 0$.

We can conclude that
A. $f$ has a local minimum at 9
B. $f$ has neither a local maximum nor a local minimum at 9
C. $f$ has a local maximum at 9
D. We cannot determine if A, B, or C hold without more information.