Question about Giants AI

I was wondering if Giants were in a compartment, and there were two adjacent compartments, both with defensive structures in them but one had higher level walls surrounding it, which would they target? Is it the distance of the defense or would they go for the weaker walls?

They would go for the compartment with the closest defences. I don't believe any troops decide anything based on the levels of buildings.

EDIT: If there is a weakened wall at the closest compartment, they will target that.