Answer:
IV graph
Step-by-step explanation:
Function: It is relation between x and y.For each x, there is a unique value of y.
Only one output for one input.
One value of x cannot have more than one images.
Vertical line test:
When we draw a vertical line passing through any given value of x and cut the curve more than one points then, the curve does not represents the function.
When a vertical line cuts the curve at one point then, the curve represents the function.
In I graph, We can see that
Image of 1 is 2.
Image of 2 is 1.
Image of -2 is 1.
There is only one output for input.
Hence, it represents the function.
In II graph,
By vertical line test, when we draw a vertical line x=1 then it cuts the graph at one point only.
Hence, it represents the function.
In III graph,
Image of 1 is 1.
Image of 0 is 2.
Image of -1 is 3.
Image of -2 is 4.
There is only one output for 1 input.
Hence, it represents the function.
In IV graph,
When we draw a vertical line x=1 then , it cuts the curve at two points.
Therefore, given circle does not represents the function.