When reflecting something across the y axis, the x point becomes of the opposite parity (for example, when reflecting (1,2) across the y axis, the result would be (-1,2)). In this case, we can start by doing this for each of the individual points.
J (1,4) becomes (-1,4) when reflected across the y axis
R (2,1) becomes (-2,1) when reflected across the y axis
A (3,5) becomes (-3,5) when reflected across the y axis
So, I think that your mistake was that you thought that reflecting across the y axis meant changing the y coordinate. That being said, the correct answer is A.