Answer: Hello there!
Let's analyze the graph.
The first thing you can see is that when x increases, y decreases. This means that our function is decreasing.
Now we need to see if it is linear or nonlinear. You can see that the function starts decreasing slowly and it gets sharper when x grows (in the graph you can see a little curve). A linear function is graphed with a straight line, and we can see that is not this case, then our function is nonlinear.
So the correct answer is Nonlinear decreasing, the fourth option.