In this case, we'll have to carry out several steps to find the solution.
To solve this problem we can graph the data and apply the vertical line test.
Step 01:
Graph 1
Graph 2
Graph 3
Graph 4
We must draw a vertical line and if it intercepts the graphed line at more than one point it is not a function.
In this case, none of the data tables represent a function.
That is the answer.