Answer:
Option: A is the correct answer.
A. g(y) is a reflection of f(x) over the line y=x.
Explanation:
We know that the reflection of a parent function f(x) about the line y=x is such that the x and the y-values change places i.e. there is a swap in the x and y variables.
Here we are given a parent function f(x) as:

Also, the function g(y) is given by:
Clearly we could see that the x and the y-variables are swapped.
Hence, the transformation g(y) is a reflection of f(x) over the line y=x.