premise: The small girl in the Hello Kitty gloves and red snowsuit smiles while sitting on a large snowball. hypothesis: The little boy is wearing a Halloween costume.
contradiction: There can either be a girl or a boy, but not both. Hello Kitty gloves and a red snowsuit is not a type of Halloween costume, so the subject can be wearing either a Halloween costume or Hello Kitty gloves and a red snowsuit, but not both.