In a linear relationship, each step of x modifies the y value in the same way.
In the first table, when x = 1, y = 3 and when x = 2, y = 6. This is an increment of 3. If this is a linear relationship, we expect the next value of y to be the previous value plus 3, thus y = 9. But in the table shows x =3 and y = 12. We can rule out the first table.
With similar reasoning, in the second table, we see (1, 2) and (2, 5). This is an increase of the y value of 3. We expect the next value to be y = 8, but we see (3, 9). The second table is not a linear relationship.
In the third table, we see (1, -3) and (2, -5). This is a decrease of -2. We expect the next value of y to be y = -7, and we do see (3, -7). The next value should be y = -9, and the table shows (4, -9). Table 3 shows a linear relationship.
To be sure, let's see the 4th table. We see (1, -2) and (2, -4). This is a decrease of -2. The expected next value is y = -6, but the next point is (3, -2). Fourth table is not a linear relationship.
Thus, the correct answer is the top-right table.