\(f(x) = x^2 - x.\) For which of the following values of a is \(f(a) \geq f(8)\)

[Vincen]

\(f(x) = x^2 - x.\) For which of the following values of a is \(f(a) \geq f(8)?\)

I. \(a = -7\)
II. \(a = -8\)
III \(a = -9\)

A. I only
B. II only
C. III only
D. I and II only
E. I, II, and III

[spoiler]OA=E[/spoiler]

Source: Veritas Prep