What they want you to do is graph these coordinates on a plane and see if it is a function. I'll use Desmos Graphing Calculator to do this.
A function is a set of numbers that increases or decreases based on a fact. For instance, if a tree grows 2 inches every day, and the numbers go up by twos, this is a function.
But as there is no correlation between the points on the graph whatsoever, this is not a function!