For the relationship between x and y to be considered a function, there must be only one value of y (output) for each value of x (input).
In other words, one value of x cannot have more than one value of y.
First, determine the coordinates of each ploted points:
(-4,4)
(-2,3)
(0,1)
(2,-1)
(3,0)
The plotted points correspond to the values of x of -4, -2, 0, 2, 3, the next point cannot have any of these x-coordinates.
The options are:
A (0,1) → the x-coordinate zero has already a corresponding value of y, so this point will not allow the relationship to be considered a function
B (2,2) → the coordinate x=2, has already a corresponding value of y, so this point will not allow the relationship to be considered a function
C (3,4) → the coordinate x=3, has already a corresponding value of y, so this point will not allow the relationship to be considered a function
D (4,2) → There is no points with coordinate x=4 plotted on the graph, if you plot this point the relationship will continue to be considered a function
Option D.