Answer:D
Step-by-step explanation: D is correct because each X (the numbers going left to right) only has one y (numbers going up and down. You could also use the vertical line line test on graphs and, as long as each line only crosses one point on the graph, it is a function.
A is wrong because one of the Xs (5) has two Ys. Remember that for points it’s (x, y) which is easy to remember because it alphabetical order.
B and C are wrong because of the same logic of an X having more than one Y.
Good luck on your homework!
