 In this video, we provide the solution to question number six from practice exam number one for math 1030 and we're given the following situation. Suppose that a connected graph has 10 vertices labeled A through J and there are two paths connecting C and D. What can we say about this graph here? Well, it is a connected graph, trees have to be connected. You have 10 vertices, so if it's a connected graph with 10 vertices, it would be a tree if there were nine edges, but you don't know anything about that. What we are told is there are two distinct paths that connect C and D together. That's in violation of the single path property, which every tree has a single path property which says given any pairs of vertices such as C and D, there must be a unique path between them. So since the single path property is violated, this is not a tree, therefore the correct answer would be B.