Answer:
The correct option is: A
Explanation:
The given equation is:

If
, then

If
, then

If
, then

So, the points on the graph of the given equation are: (0, -3), (1, -1) and (2, 1)
According to the below graph, those points are on a straight line.
Thus, the correct option will be: A. It is a linear function because the graph contains the points (0, −3), (1, −1), (2, 1), which are on a straight line.