Which of the following must be true for the graph of Y=x^2-9/3x-9

I. a vertical asymptote ay x=3
II. a removable discontinuity at x=3
III. an infinite discontinuity at x=3

Assuming you mean y = (x^2 - 9)/(3x - 9)
Factor top and bottom: y =[(x + 3)(x - 3)]/[3(x - 3)] and note that x ≠ 3.
Simplify: y = (x + 3)/3, x ≠ 3

II. a removable discontinuity at x=3