Explanation:
An exponential function is represented by function,
Where a is the y intercept and b is the growth factor.
The graph passes through (0,1) which is our y intercept so a=1
Know let find b.
The graph pass through (1,3) so plug in 1 for x and 3 for y.
So our base function is
In order for this function to shrink, we must shift the y intercept such that it is less than 1 but greater than -1.
So the only option is
Because 1/2<1