But do the categories (Animal, Vegetable, Mineral) just make no sense against the possibile answers?
The instructions for the game are at the top. A player picks a word from a card and the other player has to guess the word they've picked, starting by asking if it's an animal, vegetable or mineral.
You'd be guessing for a while before you got that the vegetable was a marshmallow.
Police are pigs, so that works OK.