Which of the following is a vertical asymptote of f(x)=2x2−8x2−2x−8f(x) = \frac{2x^2 - 8}{x^2 - 2x - 8}f(x)=x2−2x−82x2−8?
x=2x = 2x=2
x=−2x = -2x=−2
x=4x = 4x=4
x=0x = 0x=0