Notice that the first coordinates, -3, -2, -1, 0, 1, 2 
are matched respectively to       -3,  0, 3, 6, 9, 12.
Thus, as the x-coordinate changes by 1, the y-coordinate changes by 3:
We can represent this change by the following picture:
         
                         |
                         |
            (2,12) _ |
                     |
                     |
         (1,9)  _ | 
                 |
                 |
     (0,6) _ |
                                                    
So, the points are on a straight line, because:
B. Yes, because the relative difference between y-values and x-values is the same no matter which pairs of (x,y) values you use to calculate it