The table you provided represents a nonlinear function.
The outputs correspond to the inputs squared:
- For input 1, the output is \(1^2 = 1\)
- For input 2, the output is \(2^2 = 4\)
- For input 3, the output is \(3^2 = 9\)
- For input 4, the output is \(4^2 = 16\)
Since the relationship between the input and output is not a straight line (i.e., it involves squaring the input), it does not represent a linear function. Thus, the correct classification is a nonlinear function.