Answer:
B) reflection across the y-axis
Step-by-step explanation:
First to answer you need to understand the axes. The x-axis is horizontal while the y-axis is vertical. The axes are also labeled on the farthest side of each.
A reflection is when a figure is flipped over some line. In this case, the figure has been flipped over the y-axis. This can be seen because the corresponding sides of each figure are the same distance from the y-axis. Additionally, Figures 2 and 3 follow the reflection over the y-axis rule. The rule is (x,y) → (-x,y). So, the new coordinates of a figure will be the same but the x-value will be negative.