Answer:

Explanation:
we know that
The function of the graph is a exponential function of the form

Looking at the graph
we have the points
(0,20) and (1,50)
Remember that if a point lie on the graph, then the point must satisfy the function
Verify each case
For x=1, f(x)=50
case 1) we have

For x=1

so

therefore
This function is not represented by the graph
case 2) we have

For x=1

so

therefore
This function is not represented by the graph
case 3) we have

For x=1


For x=0


therefore
This function is represented by the graph
case 4) we have

For x=1

so

therefore
This function is not represented by the graph