premise: A woman holds a baby while a boy sits next to her smiling. hypothesis: A man sits with a dog and cat.
contradiction: A woman is not a man and the woman was described as being with a baby and a boy, which are terms typically used to refer to humans only whereas the man is with a dog and a cat which are not humans and would not typically be described as a baby (more appropriate terms exist - puppy and kitten, respectively) and the word boy used as a noun rather than adjective is nearly exclusively used for humans.