Step: 1
A table is said to form a linear function if the ratio of change in input to output is same through out the table.
Step: 2
In the first table Change in f(x)Change in x is not same through out. So, it is ruled out.
Step: 3
Step: 4
The change in input (x) is 3 and the change in output f(x) is 4.
Step: 5
Change in f(x)Change in x = 43
Step: 6
In the third and fourth tables Change in f(x)Change in x is not same through out. So, they are ruled out.
Step: 7
Therefore,among the choices, table-2 forms a linear function.
Correct Answer is : Table 2