Which set of ordered pairs represents a function? \{(6, -8), (2, -2), (6, -1), (8, -7)\}{(6,−8),(2,−2),(6,−1),(8,−7)} \{(-7, -8), (-3, 9), (7, 4), (-1, 4)\}{(−7,−8),(−3,9),(7,4),(−1,4)} \{(1, -2), (-6, 2), (5, 0), (1, 6)\}{(1,−2),(−6,2),(5,0),(1,6)} \{(3, 8), (3, 6), (8, -6), (1, -7)\}{(3,8),(3,6),(8,−6),(1,−7)}