A concave polygon is characterized by which of the following?

A concave polygon is characterized by having at least one diagonal that lies outside the polygon. This occurs because a concave polygon has at least one interior angle that is greater than 180 degrees, which causes the shape to "cave in" toward the interior. When a diagonal is drawn between two non-adjacent vertices of a concave polygon, it can extend outside the bounds of the figure, which is what distinguishes it from convex polygons, where all diagonals remain completely within the shape.

Understanding this characteristic helps to visualize the structure of concave polygons and how their angles and sides create unique properties that differ from those of convex polygons, where all diagonals lie inside. Knowing the definition of polygons and their properties is essential for identifying and classifying different types of geometric shapes effectively.