Read the passage from Animal Farm. Napoleon stood sternly surveying his audience; then he uttered a high-pitched whimper. Immediately the dogs bounded forward, seized four of the pigs by the ear and dragged them, squealing with pain and terror, to Napoleon's feet. The pigs' ears were bleeding, the dogs had tasted blood, and for a few moments they appeared to go quite mad. To the amazement of everybody, three of them flung themselves upon Boxer. Boxer saw them coming and put out his great hoof, caught a dog in mid-air, and pinned him to the ground. The dog shrieked for mercy and the other two fled with their tails between their legs. Boxer looked at Napoleon to know whether he should crush the dog to death or let it go. Napoleon appeared to change countenance, and sharply ordered Boxer to let the dog go, whereat Boxer lifted his hoof, and the dog slunk away, bruised and howling.

Presently the tumult died down. The four pigs waited, trembling, with guilt written on every line of their countenances. Napoleon now called upon them to confess their crimes. They were the same four pigs as had protested when Napoleon abolished the Sunday Meetings. Without any further prompting they confessed that they had been secretly in touch with Snowball ever since his expulsion, that they had collaborated with him in destroying the windmill, and that they had entered into an agreement with him to hand over Animal Farm to Mr. Frederick. They added that Snowball had privately admitted to them that he had been Jones's secret agent for years past. When they had finished their confession, the dogs promptly tore their throats out, and in a terrible voice Napoleon demanded whether any other animal had anything to confess.

Which details from the text support the claim that this passage is an allegory for the Great Purge? Select two options.

Snowball’s return to the farm as Jones’s agent
the false confessions extracted from the four pigs
Boxer's ability to stop the dogs from hurting him
the slaughter of the pigs by the dogs at Napoleon's order
the dogs' reaction to Boxer's defense against them