Think of a mirror, something that produces your reflection. The Y axis is the line that is vertical on the graph.
D) Is not the answer because it does not reflect over the y-axis.
B) Is not the answer because the figure is not reflected, even though it went across the y-axis.
C) Is not the answer because it reflected over the x-axis, not the y-axis.
Therefore, your answer is A)
The figure is reflected across the y-axis and each figure faces one another.