At a masquerade, both boys and girls wore makeup and could not distinguish between men and women. The boys only told lies and the girls only told the truth. A guy wanted to find a female partner to dance. A: "Are you guys or girls?" A said, "Or I am a boy, or B is a girl. ". which is the correct judgment the boy made? ['A and B are girls.', 'A and B are all boys.', 'A is a boy and B is a girl.', 'A is a girl and B is a boy.']