[BlitzHypercharge]

In G-2 which are aromatic?I am particularly confused in options C and D..In the D option,one ring seems to be aromatic while the other seems to be anti-aromatic due to dipole moment(termed as quasi-aromaticity).So would we call this aromatic?
And in C if we polarize the bonds and perform resonance it seems like a benzene ring is formed,so would this be aromatic?

[hollytara]

So...

A - not conjugated all the way around (there is an sp3 carbon for one of the bridgeheads) - Nonaromatic

B - around the perimeter, 14 electrons, 4n+2 number, Aromatic

C - around the perimeter of the entire system, 8 electrons, 4n number, antiaromatic. 

D - can't consider it as a single, cyclic system, so technically nonaromatic.
Each ring is "cross-conjugated" - typically highy reactive, nonaromatic substances.  Theoretically, we can draw resonance structures where the central double bond is polarized so that one ring is an aromatic cyclopropenyl cation and the other ring is an antiaromatic cyclopropenyl anion.  Being antiaromatic is always more bad than being aromatic is good, so overall....