Pls help i literally have no idea how to read a cladogram?

I think the first answer would be A B because they r from the same branch and if u look at the images they r both birds so they would hve to be closely related
Then the second one, a trait that all have would be a tail.
Then the last one, could be feathers as only the birds hve it but not the squirrel. U could even put down a beak because squirrels don’t hve a beak.

Nucleus is the organelle that contains chromosomes