Chemistry - GOC Question with Solution | TestHub

C and D are the same because D atoms do not affect the ring, while A and B are different because benzene is planar

A and B are different because benzene has alternating bond lengths

A and B are only resonance forms of the same delocalised benzene, but C and D differ in their σ framework (the D atoms sit on a $\mathrm{C}=\mathrm{C}$ or on a C-C bond of localised, non-planar cyclooctatetraene)

All four are the same compound because D atoms can migrate around the rings