The correct answer is 'their'
Here are some quotes I hope this helps.
“All animals are equal, but some animals are more equal than others.”
“The creatures outside looked from pig to man, and from man to pig, and from pig to man again; but already it was impossible to say which was which.”
“Man is the only creature that consumes without producing.
“Four legs good, two legs bad.”
“The only good human being is a dead one.”
All resources for production are controlled by one political party. It was the "pigs" that everybody did things for.
