Question

Which set of ordered pairs (x, y) could represent a linear function?
A = {(-6,9), (-3,6), (0,3), (4,0)}
B = {(1, 1), (2,3), (4,5), (5,7)}
C = {(-4,-4), (-2,-2), (1,0), (4,3)}
D = {(3,7), (5, 1), (6,-2), (7,-5)}