Since the pre-image is shown with a dashed line and the image is shown with a solid line, a transformation that represents a dilation is the second graph.
In Mathematics and Geometry, a dilation is a type of transformation which typically changes the size (dimensions) of a geometric object, but not its shape.
Generally speaking, dilations preserve the shape and angle size of a geometric figure. This ultimately implies that, the pre-image (dashed line polygon) was enlarged by dilating the image (solid line polygon) by using a scale factor of "k" centered at the origin (0, 0).
In this context, we can reasonably infer and logically deduce that only the second graph represents a dilation because the shape and orientation of the pre-image (dashed line polygon) was maintained.
Complete Question;
In the diagrams, the pre-image is shown with a dashed line and the image is shown with a solid line. Which transformation represents a dilation?