Tropolone is a compound that contains a non-benzenoid ring structure. It is an example of a non-benzenoid aromatic compound because it does not contain the benzenoid (6-membered) ring structure typical of compounds like benzene. Tropolone is a bicyclic compound with a non-benzenoid structure, making it a part of the non-benzenoid aromatic compounds class.
Thus, the correct answer is option (2), Non-Benzenoid aromatic compound.