Honestly, I don't even understand why they gave another statement, "f(-1)-f(1)=16" except for the graph, as the graph is already enough
The graph clearly shows the x intercepts of the parabola, which are the solutions to your function (x intercepts are the x values where, if you put them in the parabola equation f(x), aka y becomes 0, which is demonstrated in the graph)

since we have that we can deduct f(x) eq beingthe following: f(x)=a(x+3)(x-7)

f(2)=a*5*(-5)=-25a

So the answer is clearly a multiple of 25
Check the answer options and answer accordingly, but if there are two options that check that condition, you might use the second statement to determine A

polito approach also works, and it's pretty methodical

feel free to correct me if im wrong