Answer:
A
Explanation:
You just need to read what is on the bottom, and what is on the top and then put the right hand side of f or g where it belongs.
The question says (g/f)x
g is on top and there is no value that x cannot be. f is on the bottom of the fraction and there is a value that it can't be.
(g/f)x = (x^2 - 5 ) / (4x + 1) is the bare answer, but x cannot be -1/4 otherwise the question blows up.
The answer is A