Answer: Choice B
A reflection across the x-axis occurred. The rule is [tex](\text{x}, \text{y})\to (\text{x}, -\text{y})[/tex] the x coordinate stays the same, but the y coordinate flips from positive to negative (or vice versa).
For example, point A(1,-1) reflects to A'(1,1)
A thing to notice: Going from A to B to C to D has us going clockwise. In contrast, going from A' to B' to C' to D' has us going counterclockwise.
