List which of the 9 vertices {A.. I} are Articulation points in the following graph. Solution An articulation point is one whose removal disconnects the graph. They are (I just removed each of the vertices in turn (including incident edges) and then determined if there were disconnected components.) They are D (A and B disconnected component), E (leaves C disconnected). For the others there is still an alternative path that connects the graph. (It has cycles, so this makes sense.).