Question

which set of ordered pairs in the form of (x,y) does NOT represent a function of x?
A. {(-1,2),(3,-2),(0,1),(5,2)}
B. {(-1,2),(3,2),(-2,2),(0,2)}
C. {(-1,2),(3,-2),(0,1),(3,5)}
D. {(-1,2),(2,3),(,3,-2),(-2,0)}