Which of these statements are plausible class definitions?

Dog : AnimalCar : VehicleVegetable : CarrotBall : Football

Great job! Dog is a type of Animal and Car is a type of Vehicle. Vegetable isn't a type of Carrot and Ball isn't a type of Football: it's the other way around.

Oh noes! Dog is a type of Animal and Car is a type of Vehicle. Vegetable isn't a type of Carrot and Ball isn't a type of Football: it's the other way around.