Stefan Krzywicki (2/5/2010)
I realize this is an old question, but I'm killing time while waiting for a remote install to finish. This is a terribly worded question. The correct answer is that the 2 represents the second entry on the second level. As for the answers, it represents a node at the same level as it is the second node at a level. It also represents the parent of nodes in the same subtree, not the nodes themselves. The answer given, while one of three bad answers, is not the best response of those available.
I too am killing time, and reckon that this question and answer are appallingly bad. Essentially I agree with Stefan. The occurrences of "2" in the list of representations all represent the same node (the second node on the second level) which is not any of the options provided - all of which are wrong. Probably the answer given is the worst of the three wrong answers provided.
Tom