The equation that is given in the question is
f(x) = x^2 - 8x + 5
Now, when x = -1, then
f(-1) = (- 1)^2 - [8 * (- 1)] + 5
= 1 - (-8) + 5
= 1 + 8 + 5
= 14
So the correct option among all the options that are given in the question is the last option or option "d".