GIVEN:
We are given the following function;

Required;
To find the inverse of the function.
Step-by-step solution;
To solve for the inverse of a function f, we begin by re-writing the function as an equation in terms of y. We now have;

Next step we switch sides for x and y variables and then solve for the y variable as shown below;

We now re-write in function notation. Take note however that this is the inverse;

Therefore,
ANSWER

The correct answer is option A.