Answer:
Table C
Explanation:
This is a problem that is just process of elimination. The first step here is to organize all the x values (in each table) by value (lowest to highest). Luckily this has already been done for us. The next step is to establish slope. We can do this from any two points in the table. You find the difference between the y-values (y2-y1), then the x values (x2-x1) (where the points are (x1,y1) (x2,y2)). Now we just need to make sure the rest of the points obey that same slope.
For Example, take table A. The first two points are (1,-1) and (3,1) so using what was said before, the change in the x values is +2, and the change in the y values is +2 as well. Now applying that to the last two points, (5,3) and (8,5) we can see the slope is not the same. The change is x is +3 and the change in y is +2. Therefore we know that Table A does not represent a linear function.
The only table that has a constant slope is Table C with a change in x of +3, and a change in y of +2.