Suppose that this social network was obtained by observing a group of people at a particular point in time and recording all their friendship relations. Now suppose that we come back at some point in the future and observe it again. According to the theories based on empirical studies of triadic closure in networks, which new edge is most likely to be present? (That is, which pair of nodes, among those that do not currently have an edge connecting them, are most likely to be linked by an edge when we return to take the second observation?) Provide a brief explanation for your answer.

B D