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