Answer:
A&C is x axis B is y axis
Explanation:
The opposite of a number is it's negative or positive counterpart.
If something is reflected over the x axis there is a counterpart of an y value on the alternate point (A (9, -2) -> A' (9, 2), the counterpart of -2 is 2, 2 is a y value, meaning that the reflection is over the x axis; C (-1, -4) -> C' (-1, 4), the counterpart of -4 is 4, 4 is a y value, meaning that the reflection is over the x axis).
If something is reflected over the y axis there is a counterpart of a x value on the alternate point (B (5,4) -> B' (-5,4), the counterpart of 5 is -5, 5 is a x value, meaning that the reflection is on the y axis).