Determine which of the following relations represents a function

Select one:
A. {(-3, 0), (-3, 2), (-1, 0), (0, 4)}
B. {(-5, -12), (-3, -6), (-1, 0), (1, 6)}
C. {(-1, 0), (2, 2), (-5, 4), (-1, 4)}
D. {(-3, 0), (0, 2), (-1, 0), (0, 4)}