well technically humans are animals and they're really effin rude but an 'actual' animal i would say snakes.
i still think humans
Baboons. and Gorillas.
Tough call since dogs have no manners when someone who they aren't familiar with is passing by. As for cats they sure do love to take over the place. And hate it when you try to sit down in "their" spot. Miserable gits they are I tell ya. As for wild I'd say Tiger because they're like the uninvited guest who loves to get ya by surprise.
a big cat
The cat, they are not loyal. they even scratch their owners. talk about bite the hand that feeds you,
I think the pigeons, because even when you're at home, they are able to see you.
Evolution has already answered this question.