Final answer:
The rule for reflection is to negate the x-coordinate when reflecting a point over the y-axis.
Step-by-step explanation:
The rule for reflection is: r y-axis(x, y) — (-x, y), which is option A. When reflecting a point over the y-axis, the x-coordinate is negated, while the y-coordinate remains the same. For example, if we reflect the point (2, 3) over the y-axis, we get (-2, 3). Therefore, the correct answer is option A.