Solution:
As we can see from the graph given, the curve cuts Y axis, passes through (0,5) , (2,1) and appears parallel to X axis.
Also, you can see that curve is decreasing and after it crosses the point (4,0) it becomes parallel to X axis.
As you can see from the graph , the general equation of curve will be
f(x) = [tex]a^{-x}[/tex]
There is no function in the option given which has a negative exponent.
