The function f is twice differentiable, and has no points of inflection. If f(6)=3, f'(6)=-1/2, and f''(6)=-2 which of the following could be the value of f(7)? 2, 2.5, 2.9, 3, 4.

I can rule out the last two options easily but I feel like I'm missing an important detail than besides the function is ccu and decreasing. The answer's two, but I don't see why it could not be 2.5.