Deduce the structure of each compound from the given information. All unknowns in this problem have the molecular formula C8H12.

A) Upon catalytic hydrogenation, unknown X gives cyclooctane. Ozonolysis of X, followed by reduction with dimethyl sulfide, gives octanedioic acid. Draw the structure of X.

B) Upon catalytic hydrogenation, uknown Y gives cyclooctane. Ozonolysis of Y, followed by reduction with dimethyl sulfide, gives two equivalents of butanedial. Draw the structure of Y.

C) Upon catalytic hydrogenation, uknown Z gives cyclooctane. Ozonolysis of Z, followed by reduction with dimethyl sulfide, gives a three-carbon dialdehyde and a five-carbon dialdehyde. Draw the structure of Z.