Which set of ordered pairs does not represent a function?
O {(7,5), (-6,0), (8,-9),(-1,-9)}
O {(0,–2), (3,9), (-5, -1),(-9,9)}
O{(-5,-4), (1, -1), (2,5), (3,5)}
O{(-9,9), (-6,0), (-9,8), (-1,-2)}